That's the thing, working as one of the first people at the startup is a pretty intimate close team (or at least should be). There's a lot of "safer" and or more compelling ways to pull folks in. a) Offer a moderately accelerated vesting schedule for early employees. b) have the initial work be as a sort of moonlighting in terms of time commitment (more suitable / appropriate when either taking a bootstrapping approach and or building out the MVP.) c) seriously, it's your first hire, you folks will likely (and perhaps unfortunately)spend more time together than you will with your respective significant others.

Point being, yes it's "just business", but if you're not setting things up to be awesome for that first hire, are they going to be sufficiently awesome do as to be worth spending so much time together? And if they're that great, how much do you wish to ensure that you guys are likely to choose to work together again?

I'm likely way over reacting, but still, it's a matter of some importance, exercising choice over who you spend time with, so why settle for less than awesome or treating them awesomely?!