I've found there were many reason these clubs were raided, and most were not to shut them down.

Sometimes it was just as "a show". In these cases, the owners would get notice of the raid and none of the equipment would be damaged or confiscated (or if it was, it would be returned). The police would get to say they were doing something against vice, the owners would pay their small fine and go about their business.

In the IOTD above however, these I would definitely qualify as "nuisance" raids. When equipment is destroyed and owners arrested, there is a definite cost in both time and money. We're not talking about big crime families with millions of dollars here. The cost of a couple roulette wheels and trial lawyers might be enough to put some guys out of business.