They collect their pay at the end of the month either way, as long as they don't get laid off of course. Do most people actually care about the 'mission' of the company or do they just want a nice pay at the end of the month and to enjoy the work/journey along the way.
Personally if i got paid well, enjoyed the work and got to play around with tech that i thought was interesting, I wouldn't care if Meta itself was successful in what it was trying to do, i'd only be a small cog in that machine.