Early access, sounds to me like you are paying to be a beta tester.

And paying for a demo? Unless it's a short game that isn't part of the full game, then no. A Demo is short for "demonstration" and is meant to try and sell the game, and for me it should be free. It's a "play a bit and see how you enjoy it".
So I would not pay for for EAV or a Demo. But then again, I'm the wrong target, since I don't buy games anymore.

Here's a good exemple of good sales tactic (though it's a book):
A few weeks ago, there was this "book week" where children from 9 to 12 could go to a book shop and get a free book. So, since our son is 9, we went and got this free book. He started reading it, and thought it was rather boring, but since he had nothing else to do (I had punished him with a week off computer/tablet/tv) he continued reading the book. The day after it was starting to be interesting and by the time he was done reading it (the end of the week - it was a rather big book might I add), he was hipped and could barely wait to read number 2. Number 2 will be lunched on the 19th so I decided to get it and give it to him for his birthday (the 20th). Had he not gotten this book for free, he would never have read it and I would never have bought nr.2 ... and will likely get nr.3 as well (think i's suppose to be a trilogy).
So free book = more sale... Probably a good deal for both the author and the publisher.
