Some have, most haven't. And those that have had mostly adopted the philosophy of "Every token spent is a a token spent well; except the ~10% of staff that abuse/misuse them".

And with that philosophy, you naturally want to set the per-person budget at around the 90th highest spender. Which is what most did (some version of it).

So very few companies have actually set a truly restrictive policy. Just a "don't abuse this" policy. But that will change IMO.