That's messed up. They probably got sued at some point. But, it's corporate, so no surprise. Hopefully it's not a hockey puck your biting in to.
It depends. Restaurants must notify patrons if they serve pr allow undercooked beef. This is federal law. Some restaurants don't want to bother with this or take on that liability. If there is no disclaimer, then this is indeed the law per federal statute.
Some restaurants have their own policy regarding how they cook their meat, however if you wanted a burger cooked well done I can't imagine that ever being an issue.
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