How do you convince them?
You dont. lol
No really, the biggest headaches come to me from these matters. They first believe that you're a big loser, then when you shut them up with proof, you get all sorts of 'get a real job!' so I'd simply stay clear. I dont need to prove to anyone anything. You work, you make money, you're happy. Cool! Trust me, talking about IM matters in general with 'muggers' (lol, I dunno how the hell did that pop up in mind. In Harry Potter, it means 'non-magicians' if you dont know..lol) So back on topic, talking to muggers about IM have never yielded but trouble for me.
Edit: seems that pretty similar replies to mine were posted before I hit submit.