If microstock went belly up tomorrow, my life (well my income) wouldn't be affected since I make very little with it.  My life would definitely be affected because I would have lots more spare time!  

My plan is to always keep my day job that pays well until I can retire (hopefully not more than 10 more years).  If microstock and stock in general survives, it will be a nice extra retirement income.

The same for me exactly!!!

My backup is graphic design.  I can be freelancing right now, and making in a week what I make in a few weeks of microstock sales, but I'd much rather do stock   Less stress, no dealing with people.