Kickstarter rage, basically. It will be interesting to see how it plays out when the payments in question are big enough to get lawyers involved.
Don't go handing over money without some recourse if things fail to materialize.
Don't sell something you can't deliver, most especially to bypass accredited investor laws (by selling tickets versus securities). Don't misappropriate your customers' escrow accounts (the article specifically mentions these funds were to be held in escrow). This applies whether it's a $100k ticket to space or a $200 piece of electronic kit on Kickstarter.
I'm guessing that won't be acceptable to Xcor because they intended to spend the pre-sale money on R&D.