Each state sets it's own rules for running gaming establishments. Some of them mandate the destruction of obsolete chips (but drilling, notching, cancelling might be ok). I think New Jersey has the state redeem old chips at face value if they aren't otherwise destroyed. Nevada requires that the void chips be destroyed. Some states have such difficult regulatory rules that companies like the chip room will not be able to resell void chips. And then there are other states where defunct chips can be resold.
There will be exceptions and unique cases that bend/break the rules, but some of the best prospects for massive chip sales are in states where it isn't likely to happen. I can only dream of the sets I'd have if the failed & rebranded Vegas rooms could resell the void chips.
DrStrange