I think maybe when u get the 30 day trial, it should give you a temp 30 day forum account, and when the trial runs out, the account cannot be used until you buy a version, and then you have your forum username nicely reserved too. I think that when your on the 30 day trial, thats the hook period, it sells copies when people in the 30 day trial think: Wow, i can really make this work! What better way to get people into blitz than enabling them to make nice things? And how can they do that if they cant consult the community for help?
Now that's a good idea. You can pirate the software, but if you want access to this excellent tech support forum, you gotta pay for it.
TBH, I really don't think piracy is such a big issue (at all, but even less so) with affordable programming packages.