Something to consider is that often I'll test drive a product with a few people on the cheapest possible plan, or free trial, for a month or two before rolling it out. Being able to do that really quickly, without setting up hosting, is a big benefit. If a customer can jump in straight away for a month long trial it might increase sales.

Also, I'm not in the market for this right now but I keep a list of products I've seen and liked. The need to sign up for your demo stopped me looking at it. Consider if you can remove that crucial barrier to people seeing your app. Something like read only, a preset user, or generate an account automatically with a disposible email address.