Sigh... Anyone, of any gender, is probably going make this joke regardless of the gender of the other party.
If you can't laugh with the joke you probably shouldn't be in the sex industry. At all.
Nothing to see here. Move along.
I'm sure you have a female in your life who is important to you. A wife, daughter, mother? Would you be ok with an investor talking to your daughter like that? Joking that she demonstrate a sex toy for him? I would be absolutely furious.
This is not something to just ignore.
Buy anyway: passing joke? That's fine. Absolutely normal.
If the person demanded a demonstration that would be completely different.