While a number of projects certainly are treated this way, it is this attitude from users that has ruined my enjoyment of backing projects.
Backers are certainly not investing in the traditional sense since they do not get any share of profits, etc, but once upon a time, they were investing in having an idea become available. I backed many projects just to see the idea come to be. Ideas that could not get funding through traditional means. Between a mix of people who were trying to get a fast buck and backers loudly complaining that their "pre-order" was taking too long, it just became too much trouble.
People could no longer take chances on interesting things because they had to provide constant assurances to backers that they would get their loot.
A project pretty much has to be good to go now which has made it difficult for new people to get into the game with fresh ideas. There is too much risk those projects might fail and backers will come screaming for their money back.