Why do girls think it is weird for a guy to like cute undies?

like thongs or low rise bikini briefs. I like skimpy undies. I think they are cute and y. I am in good shape, so why not wear something that shows off my body. I am straight by the way. I just don't understand why girls want us guys to wear boring boxers. why do girls think it is "gay" for a guy to like cute undies.