Reason enough for existing fans, and people who's interests closely match the project. Is that where the majority of money comes from? No, it is not.
Do people who were a little iffy on a project in the first place care if it doesn't get funded? No
But an exclusive alpha to the game they don't care about (and for $90) is a good reason? the majority of the money comes from people that wouldn't care if the game is funded but are persuaded for an unfinished version (again, for almost $100) of it? i thought that really high tiers with alpha/betas are especially for the existing fans and people who care enough to play a game in alpha state, silly me, is actually for people in the "meh" category. I mean, i can see people trying a beta (if is close to going gold) for FREE for a game they aren't really interested in, but an alpha? and a really expensive one? That's what convince people who are iffy about it, really?
what exactly would be the justification that that must be cheaper than during the kickstarter?
Because the game was already founded? let me turn that question back at you, what exactly would be the justification for charging ANYTHING for an alpha? Sure, is their game, they can make a $15 DLC for every section of the option menu if they want, but there is a reason why almost every game in early access is cheaper than the regular price, you are giving money to the developers for a game that is not out (or even finished) so you can alpha-test it. An alpha make sense as an incentive to get a higher tier (and again, only appeals to people that care) or an add-on in kickstarter because the nature of it...
selling it cheaper to everyone else is a tad rude.
The problem boils down to if kickstarter is a store where you can buy and sell stuff or a site to Crowdfund projects
Spoilers: is not a real problem, is the second one, this is an empirical fact, there is a "What is Kickstarter?" section in the site, highly recommended reading, the second you are using "buying" or "selling", you are wrong. The ToS is pretty exact with its words, you are "pledging" and what you get is a "reward" for supporting a project. Anyone who would feel offended is wrong in a fundamental level about his approach to kickstarter and have a really toxic ideology
