Maybe it's because I grew up on the east coast but I don't think flip flops should be worn everywhere. I don't understand why someone would wear flip flops to a movie premiere. There is an article in today's NYTs about how Hollywood dresses down.
The weather here has nothing to do with it. It's hot year round in the Caribbean and people dress up more. My friend Claire and I were at a restaurant last week and this women (maybe in her early 20's) was out to dinner with her boyfriend and his family. She was wearing hot pink low rider sweatpants that were too long with her thong showing, flip flops and a cropped spaghetti-strap top. Call me crazy but I wouldn't wear that to a nice restaurant.
I'm trying not to to dress like a slob all the time but it's hard. When I dress like a slob I feel like one. So in order to continue trying to break out of my post Italy funk, I will dress the way I want to. Of course I'm not going to start wearing suits (I've worn a suit maybe twice after moving to Los Angeles and that was when I had an interview at a studio 6 years ago.) but I will try to put a little more effort into what I wear. Like they say, "when you look good, you feel good."