My experience with hickeys were with insecure high school chicks that wanted to "claim" their man. So in that way, it's trashy. I don't want to see someone's hickeys. It's your business, have fun, but I don't want to know.
Also, it depends on intent. Sometimes my partner will put a hickey on my butt just for kicks. And it is funny to us. But we don't do hickeys other than that rare, funny, occasion.