Not that there wasn't booing before, but as societies become more liberal, people tend to lose the internal checks that breed a sense of civility and restraint.
The lack of basic civility in Seattle is breath-taking. My current pet-peeve are the increasing instances of people bringing their dogs into restaurants and grocery stores.
WTF? When did THAT become OK?
I mean sure, it's fine in places like Alaska or Arizona where the weather is so extreme that leaving a dog in the car can be considered cruel. Businesses in places like that tend to be prepared for dogs.
But in temperate areas? Where no one's prepared for it? It's like the employees are scared to say, "Excuse me but, we can't have non-service dogs running around our store. We would appreciate your taking it outside."
I was in my local Home Depot the other day when I smelled the distinct oder of DOG POOP!! Sure enough, some old guy was cleaning up the mess on isle 4. Disgusting, and I told him so.