I used to own a business once, even a restaurant eons ago, and if I recall, if a business has rules, you cooperate, dealwiddit.
If you hate the rules, don't come.
I mean, I hate masks as much as anyone else, but the couple times I was at SL recently and ate, I really didn't find it outrageously uncomfortable to wear the thing under the chin as requested, jeez, dude, find some bigger fish to fry, learn this English word : PETTY.
Also, speaking of fish, SL has the best fish sammich in all of San Jose, and if you go there and get one, you can use the mask to wipe your face, and if you extend it out from the chin, it'll catch food before it smears all over your shirt showing different fish, so it prevents you from showcasing fish and smelling like one, too.