The general idea is that, as in any business, there is a series of people who benefit from an action, which in turn benefit someone else, and so on, most probably benefitting the first one.

Take an example that is being shared quite often in social media, it says that we should pay in cash, as the USD 50 we pay in a store allows the person to take those 50 and pay in the local market, and, in turn, allows the owner to pay for meat at the butcher's with that money, which will allow the butcher to use that money at the first store to buy. However, if instead of using cash, you use credit cards, the banking fees appear, and that money becomes less and less until the cycle is finally broken.

The same notion applies in crime and illegal activity. Barrabravas engage into a series of illegal activities: drug dealing, illegal reselling of tickets, illegally charging for parking spaces near the stadiums, bribes, etc, and many different groups and individuals benefit from this cycle. Now, if the police were to interfere, then the situation would be terminated... and hell breaks loose!

Hope it's clear!

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Note added at 4 hrs (2024-01-14 20:53:31 GMT)
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I've just seen that patinba provided a similar answer. It's the same idea, but I think it may be a bit too formal, but that's just my take on the subject.

Cheers!