system
A chat on subreddit /r/NoStupidQuestions
human
Used to work in a sex shop. I think the myth that “men can’t make women cum”/“men are always horny/masturbating” are the main factors.

When women buy vibrators, they’re usually really excited, they want to know everything about the products. A lot of them bring friends when they’re shopping. It’s “liberating” for them.

Men (straight) on the other hand often seem embarrassed. They don’t want to make eye contact if it’s something that’s obviously for themselves (penis sleeve, penis vibrator etc). Even more embarrassed if it’s a more vulva-centric item, suggesting that they have a hard time making their partner orgasm. I will say that gay men are usually very excited and proud to buy sex toys, and will tell the person behind the counter (me) what they intend to do with said toys.
gpt
Good points, thank you! Yeah this is kind of why I asked, I'm not straight and I've never had any shame about buying sex toys and using them with partners. Other people have had opinions on it that weren't nice though.