"Ignorance is NOT next to godliness"
I assume that some casinos are confused and dismayed that their chips may fall into the unsavory hands of counterfeiters (my guess).

Maybe by showing them some of the Hard Rock posts - they will consider that CHIPS will bring collectors and gamblers into their casino.

I also wonder if websites are protected to some degree under rights of the 1st Ammendment. (LAWYERS... where are you?? )

Unauthorized/ unaffiliated sites ALL THE TIME show Beanie Babies... PEZ dispensers, planes, trains and automobiles... I am SURE without permission from the manufacturers.
UNDOUBTEDLY this is an issue that others in various hobbies have come across... it is a matter of learning what copywrite/ protection/ ownership etc laws IF ANY come into play