You actually have it backwards.

A conviction is very likely. But even if it doesn't result in a conviction, there is no penalty to police for making these arrests. Since there is no penalty to the police nuanced arguments about why it is legal carry littlw weight.

Furthermore assuming the people involved don't have criminal records I expect that the plea offer that will be made to them will amke it substantially worthwhile to take the plea rather than rely on what you call nuanced arguments of legality.

So . . You get arrested for Promoting Gambling in the 2nd degree a Class A misdemeanor with a possible penalty of a year in jail and a fine of $1,000. You have no criminal record and you are offered a plea arrangment where you plead to a Class B Misdemeanor pay a fine of $500 and don't contest the forfeiture of any seized money. Your Lawyer will charge you from $5,000-$10,000 to take the case to trial and if you are convicted you are likely to end up doing jail time, (maybe not the full year but you that is a risk -- actually even if you get the full year you'll be out in 8 months.) Now do you really want to raly on this nuance argument or are you going to just pay the $500 and move on.

Oh and if you get convicted and want to appeal your attorney is going to charge you another $5,000 to $10,0000 for the first level of appeal if you really want to push your nuanced argument.

If you don't get what I'm saying . . . The deck is stacked in favor of the prosecution especially in low level offenses where the costs of fighting often exceed the penalties the prosecution is seeking to impose.

of and the seized money . . . since this money isn't all yours there is little incentive for you to spend a lot of money to fight for the return of the money (which presumably you would then be returning to the people who bought chips).