^What you mean like get it for cheap off of eBay or something? That's how I got DOA5. I was contemplating buying NG3 but something told me to go on eBay really quick. Got it for $7 bucks. The Ayane/Hayate vers. But now there's only one for PS3 and its going for $25 last time I checked.
The thing I fear about this RE6 demo is that its highly anticipated and there could A. Not be that many demos available for sale, B. price gouging/scaming. I'd just buy the game and trade it in quickly to get a high value to be safe.
Just take the Gears 3 Beta, they packaged it with Bulletstorm because they knew that by itself, Bulletstorm wouldn't have sold as many copies as it did.
Luckily, the majority of people who bought Bulletstorm purely for the Gears beta found out it was actually a really fun game - but seeing as the FPS market is much bigger than the RPG market, it's going to be harder for a lot of people to like Dragon's Dogma if they are only interested in the Resi 6 Demo
Also, my Dad owns Capcom, July Demo is only for DD owners on 360