I think it really comes down to what you seriously think you might be bugging out from. Leaving because our house burnt down is going to be different than if there's a rail crash with a chemical spill, and significantly different than leaving because one of the nuclear power plants around here melted down, don't ya think?

Another thing to consider: if we ended up at my in-laws for any significant amount of time, setting up my camping gear in their backyard would become more and more attractive as time goes on.

We've got two set-ups for a reason, and I suspect that a combination of both would be the most likely outcome. We've been stuck in a hotel out of town due to a vehicle breakdown before, while on the way to a camping trip, and our camping gear came in just as handy as our typical suitcase stuff. We just didn't need the tent.