I agree with Knuck. There needs to be a reasonable return policy. Now... I also understand that it would get crazy abuse. Like people that buy a game, play it in a day or two and then return it. It's not like you can buy underwear, wear it for a day or two and then decide you don't like it. So there has to be something more.
I have gone down the torrent route in the past but often it's because the demo isn't sufficient to give something a real test drive. And I have, on several occasions, ended up buying the software or donating to the company after using the torrented version if it's worth it.