Paris LV roulette jetons were denominated... but they were the exception.

Regarding roulette harvesting, it could get a player barred from the casino (though rare). That settles the issue for me.

Over the years, I've known a couple of chip collectors who work in the industry and held "'work permit" cards, or whatever they are called these days. They steered clear of roulette collecting, I assume because they didn't want to jeopardize their status with Gaming Control and/or their employer.