I've seen these shops for years and wondered how they stay in business with so much competition from the same types of business and all of them with very few customers. I think they can found everywhere.
Clearly Trading Standards Officers do not have the clout to confront them and the police can't unless they have evidence of illegal activity. HMRC, on the other hand, can investigate any business they suspect of tax evasion. These businesses that are still running on a cash basis could be monitored if HMRC chose to.
It seems to me that all the agencies involved with investigating these types of crimes are focussing on the top of the chain which is a long process, often taking years. And when they do eventually arrest those at the top they are immediately replaced by the criminals below them. Focussing on the top tier doesn't actually work. But like everything else in this shithole country there isn't sufficient funds to tackle these problems at all levels.