I don't think some people get the idea of a theme party. I have a group of friends that are really into theme parties. They go all out, above and beyond, decorations, costumes, you name it. I went to a "Beach Theme Party" for New Years this year with a different crowd of people. I only knew two people at the party, not counting Doug. So I was expecting everyone to be wearing shorts and a tank top, the heat up to 80 degrees. Turns out, these people do not know what theme party means.
I got decked out in my wet suit and a towel around my neck. Doug wore shorts and a hawaiian shirt. I felt like I was in one of those dreams where people invite you to a costume party and you're the only one wearing a costume. There must have been 30+ people there and me, Doug, and one of the other people we knew were about the only ones dressed up in beach wear. Oh there were a couple of people wearing flip flops... along with jeans and a sweatshirt. Come on people! I did get a few nice comments on my wet suit though. :)