Every time I visit India, more and more international brands seem to have set up shop. A few months ago while waiting in my dentist's office, I leafed through the tattered copy of a women's magazine. The inner front cover was graced by the ubiquitous fairness cream advertisement. A flawless pale face smiled at me from inside the front inner cover, promising double perfection – less spots and radiant skin. The product: L'Oreal Paris White Perfect Re-Lighting Whitening Cream.

You know L'Oreal. The "Because you're worth it" company. The world's biggest beauty products manufacturer, whose product lines range from the Body Shop to Soft Sheen Carson, the leading haircare brand for women of African origin. L'Oreal faces include Beyonce, Penelope Cruz and Aishwarya Rai. In a recent glossy report about sustainable development (the cover is a portrait of a Mauritanian woman), L'Oreal devotes several pages to its commitment to good corporate citizenship and in particular to "skin and hair diversity".

In the meantime, young brown women in India, please buy our whitening cream – 16% increase in brightness in one week, 32% increase in luminosity in four weeks, and intense action on your brown spots.

And that is downright subtle when compared to Pond's, which recently came up with a television advert in which the dark woman wins her lover back after applying Pond's fairness cream. The ad ran in India and elsewhere in Asia (with a different cast) but nowhere else in the world.

Certainly, the fetish for white skin goes a long way back in Indian society. Matrimonial ads routinely call for "fair" brides. Bollywood heroines tend to be light-skinned. Fairness creams and home remedies for dark skin are legion all over the country. But when international cosmetics companies enter the fairness creams market, peddling in India products that they would not dare stock in the aisles of the politically correct west, there is a layer of hypocrisy that is dangerous to ignore.

As emerging economies all over the world open up their markets we hear a lot of buzzwords around global brand-building. Multinationals are falling over themselves trying to "think globally and act locally". Here is a case where acting locally has been manipulated into a calculated double standard. Of course, all beauty advertising caters to culturally relative neuroses of what is beautiful but surely even the most naive marketing chiefs at L'Oreal must have had a glimmering of doubt – "Wait a minute, is it racist to promote whitening? Would we put these words in a billboard on Times Square?" – before they cleared the words, "White Perfect Re-Lighting Whitening Radiance".

This begs the question: what are the ethics of global branding? As multinationals become more powerful than governments, what are the core principles that we as global and local customers should be able to hold them to? Considering that some of these companies have GDPs higher than that of small countries, it is scary how unregulated international advertising is. It is left to the individual customer to educate herself and make socially responsible choices.

The good news is that customers around the world are increasingly looking at corporate social responsibility as a deciding factor in their buying decisions. Douglas B Holt, a leading scholar in the field of cultural branding – he has brilliantly exposed the vast difference between Starbucks' self-promoted narrative as a progressive brand and its lobbying against Ethiopian coffee farmers – concluded after an extensive study of global branding that consumers may associate global brands with good quality but also expect global companies to adhere to higher ethical standards. His research revealed that "people may turn a blind eye when local companies take advantage of employees, but they will not stand for transnational businesses such as Nike and ExxonMobil adopting similar practices".

Now if you are interested in irony, here is a really good one: Douglas B Holt happens to be the L'Oreal professor of marketing at Oxford.

It is clear that multinational companies have a lot of resources to spend on whitewashing and greenwashing themselves. But at the end of the day, unethical global branding might be the same thing as short-sighted brand-building. As customers become increasingly aware that purchasing power is a political power on par with voting, and the internet makes it difficult to keep secrets, multinationals who talk the talk but refuse to walk the walk will find out that pouring millions of dollars into creating elaborate corporate mythologies cannot replace consistently principled branding. Customers are not stupid. It is a lesson that Nike learned the hard way.