Barry,

You have the right idea, and so does Greg. Either you take roulette chips by entire stacks of 20, or you just take a couple. If you take the entire stack, they can't tell some are missing by an uneven stack (unless they count stacks, which they never do). On the other hand, if you take 1-2 chips, most dealers will assume you have tipped the waitress with them. Of course, taking only a one doesn't leave any chips to trade.

One more thing. Many times, especially at small Indian casinos, the roulette chips are generic - meaning they have no distinguishing marks linking them to a casino. These are rarely collected (except for possibly by nuts like Susong).

Take care,
Ed