So, I'm going to put this person to the wall of shame. Because I think they're most likely running a nulled forum since they can't purchase an add on due to not having a legit Xenforo license. Now, I doubt this person is using a real name. But here we are, this is the most odd PM I received in a while. Perhaps I should take on the offer and run away.
Oops, I expected a different type of "questionable" since I'm a woman, but okay. My answer to both would be YES, I have. I try to not engage with people who do that or I am very cold and straight forward in my response. If they're spammy, they are kicked off the site.
Thankfully I never had anyone come to me and beg me to buy a plugin for them. I only got spam, nothing too out of the ordinary just links to suspicious downloads which of course I didn't click on.