Why do people thinkit's alright to push their fetishs on people?

Why do people think its alright to message, and continuously try push their fetishes on you after telling them you're not interested.
I don't judge people on what they're into (unless its obviously terrible like child abuse, etc), you do you,l. But most on this site don't seem to know how to take no as an answer.
I end uo blocking them, but then more just keep messaging, lol.