I'll give you early access to that car over there, but there's no wheels, no engine and no paint job on it. It has the frame though, can you give me more money please, so I can design and manufacture all the doors for a real start? The thing is I have that nice idea in my head but I don't have enough money.
I really have a hard time with "early access" and Pre-Alpha impressions (seriously what sort of ideas can anyone sane of mind can build from a game that's been coded for maybe 2 or 3 months if you're lucky?). Additionally I have lack of trust with almost anything of that nature. What if it fails and never even reaches "Beta" at all? There's been decent, and even good exceptions here and there but generally-speaking it's a question of trust and risks. I guess that we do need some gamers (consumers) out there with enough money to spare on things like that to help the independant studios complete their "cool idea that costs too much money otherwise".
But I won't be part of that club. I'll be part of the "wait until the 'final' version, then wait a couple of extra weeks or possibly months after the release when patch #17 has been released and most communities have expressed their honest opinions, and uploaded their personal video review-without-too-many-spoilers before making my decision and actually buy the game" club instead (I'm saying this because, since a few years now it IS also a risk to buy a 'final' version of a game on the actual release date, day-one purchase does not guarantee that the game you buy is actually "out of Beta" anymore, those years of gaming are gone).