Image copyright Starbucks Image caption Voters in the Philippines could get a free Starbucks drink if they showed their inked finger

If you want to know what coffee and elections have in common, ask Starbucks.

In May, the US giant ran a campaign in the Philippines called "care to vote", which rewarded customers with a free drink if they turned out to vote in the country's general election.

Having visited a polling station, all customers had to do was show an ink-stained voting finger to a barista in order to get their complimentary coffee or other beverage.

"Our intent was simple," says Keith Cole, head of marketing for Starbucks Philippines.

"By helping to increase voter participation we believe more people will have an opportunity to make their votes count."

From campaigning on voting rights, to sustainability, healthy eating, and gender equality, businesses are increasingly speaking out about societal issues, in the hope of influencing - and improving - our behaviour.

The aim, they say, is to use their power and influence for good, and not just for profit.

But with corporate scandals never far from the news, can we seriously take their word for it?

Real beauty?

The idea that brands might encourage us to be better citizens is not new. UK chocolate manufacturer Cadbury and US carmaker Ford invested heavily in the towns where their employees lived in the 19th and 20th Centuries, and in return expected workers to uphold certain values - both in and outside work.

But today such efforts tend to be more consumer-facing, the aim being to promote social good while encouraging brand loyalty.

Take the Dove Campaign for Real Beauty, which has been calling for a wider definition of female beauty since 2004.

Image copyright Dove Image caption The Dove Campaign for Real Beauty wants all women to celebrate their bodies

Run by Anglo-Dutch consumer goods giant Unilever, the owner of toiletries brand Dove, it aims to celebrate women of all shapes and sizes.

Unilever says the scheme has "pioneered the use of attainable images of beauty" in advertising, using women "with real curves".

At the same time, Unilever saw annual sales of Dove products reportedly increase from $2.5bn (£1.9bn) to $4bn in 2014.

Responsible drinking

Another example is Dutch brewer Heineken, which has promoted moderate drinking in its advertising since 2011.

Heineken PR manager Milly Hutchinson says that the firm believes it has "a role to play in society", and the "perfect platform to spread the message of moderate consumption".

Image copyright Heineken UK Image caption Heineken is encouraging moderate drinking

However, she adds that the firm is also reflecting a "discernible shift in consumer behaviour", as its own research shows that a majority of young adults now limit the amount of alcohol they drink.

A Heineken survey published in January found that 75% of drinkers aged between 21 and 35 limited the amount of alcohol they drank on the majority of their nights out. The study was conducted across five countries - the US, the UK, the Netherlands, Mexico and Brazil.

Charlotte West, from UK charity Business in the Community - which encourages businesses to make a positive difference to society or their local community - says it is true that a growing number of firms are making their campaigning voices heard.

She says that the trend has been partly driven by the rise of social media, which has empowered consumers to hold brands to account in an unprecedented way. And so firms are having to respond.

"More and more, customers want businesses to stand for social impact, and in our changing world they have to play a bigger role in solving societal problems," she adds.

However, Laura Spence, professor of business ethics at Royal Holloway, University of London, cautions that "there is bound to be some enlightened self interest in these campaigns".

She adds: "Companies can see that being associated with a certain practice reflects well on the them, and might bring in additional customers.

"But they can risk seeming preachy too, which doesn't always play well."

Voting rights

But what of the growing trend for businesses to get involved in campaigns with less obvious corporate benefits?

Examples include Apple chief Tim Cook's campaigning on gay rights in the US, or Facebook's chief operating officer Sheryl Sandberg, who advocates gender equality.

Ice cream maker Ben & Jerry's (which is also owned by Unilever) even launched a new flavour in May called Empower Mint (peppermint ice cream with fudge brownies and fudge swirls) as part of its "democracy is in your hands" campaign for increased voting rights in the US.

Image copyright Ben & Jerry's Image caption Ben & Jerry's is campaigning about voting rights in the US

Among other things, Vermont-based Ben & Jerry's wants to see an end to voters having to produce ID cards when they go to vote in numerous US states, saying this disadvantages people from the black community, as they are less likely to have the required identification.

But businesses can incur our wrath when they speak out, too, as happened to Starbucks with its #RaceTogether campaign last year.

Hoping to encourage racial tolerance, the company encouraged its baristas to start conversations about race with customers, and to write #RaceTogether on takeaway cups.

It followed national protests in the US over police killings of several black men.

But there was a huge backlash on social media, with many calling the campaign disingenuous, and others saying they did not want to talk about race while being served coffee.

Image copyright Starbucks Image caption Starbucks had to stop its #RaceTogether campaign

The campaign was quickly dropped, but Starbucks says it has learned from the experience, and stands by its desire to get involved.

"Any time you take on a controversial topic there is risk involved, but we knew race relations was an important topic," says a spokesperson.

"We felt that we could use our scale and footprint to help create a safe space for these conversations to take place across the country."

'Needs authenticity'

Vicki Loomes, an analyst at consultancy Trendwatching, says: "If companies are going to campaign on an issue, it needs to be something they are invested in long-term and aligned with what they do."

She adds: "It cannot be a three-month marketing campaign, talking about something like immigration, simply because it is the most newsworthy topic going around."

Ms West of Business in the Community agrees. "People can see through rubbish, so it has to be authentic and honest and relevant to your brand."

Clearly companies must strike a delicate balance when weighing in on social issues, but it seems that we would rather they tried than did nothing at all.

"Businesses have realised they can't just grow and take away from people," says Ms West.

"They have to grow while giving back, which I think is a really responsible capitalist approach."

Follow Business Brain editor Will Smale on Twitter @WillSmale1