Earlier this week Millwall joined Bolton and Sheffield Wednesday in rejecting a sponsorship offer from one of a growing group of payday lenders springing up in our communities and exploiting the most vulnerable. Some reports originally identified the company behind this offer as QuickQuid, who advertise its short-term rates at "only" 1,734% APR. Millwall have since issued a statement denying that the offer was from QuickQuid, but confirm that they would not accept such an offer [see footnote].

The decision to turn down advertising from payday lenders is not a one-off from a very proud club. The club, like its supporters, has a proud history of solidarity with its working-class support. Millwall has consistently stood shoulder to shoulder with working people fighting for their communities, like it did with the miners, the dockers and the printers in the 1980s. Then, as now, Millwall is at the forefront of working with the community. It was the first football club to establish a food bank and has taken a lead in mobilising people and raising thousands of pounds in support of the fantastic and on-going campaign to save the A&E department at Lewisham Hospital.

So it's no surprise that Millwall took the bold step at great expense to the club to turn its back on the money of payday lenders. Not so long ago, many of these companies would have been described as "loan sharks" – employing thugs to knock doors on our estates. Yet now they're carefully crafting their reincarnation as legitimate businesses on our high streets and TV screens. They want football clubs to legitimise their shady practices, when in reality all they will do is add to the poverty of our community, while charging obscene levels of interest on growing debts. They are not welcome.

We at Unite have been in regular discussion with more than 300,000 of our members since 2011, tracking the impact of recession and austerity on real Britain. With falling wages and rising costs, tens of thousands of people are now borrowing the equivalent of a week's wages every month. We know that ordinary people are getting deeper and deeper into debt and falling prey to payday vultures as they struggle to meet the obscene cost of rent and energy, food and transport.

This is why we are backing Millwall's stance and the MP Paul Blomfield's bill to regulate these lenders. It would stop prime-time ads and the enticement to roll over debt into even larger loans at extortionate rates of interest. It will also crack down on harassment and intimidation on collection.

What we really need are good jobs and decent wages, capped energy prices and homes at affordable rents. Raising the minimum wage by £1 an hour and introducing a living wage would be a good start to rid these payday loan companies from our communities. Millwall has done its bit in this fight and must be congratulated. Its values are rooted in those of its community; solidarity, dignity and respect. As a lifelong supporter and season ticket holder I am immensely proud of what Millwall has done.

• This article was amended on 28 June 2013 to make clear that Millwall have denied that they received an approach from QuickQuid

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