If everyone votes to reallocate everyone elses blocks all the time, then you'd end up losing your own coins too, so this doesn't seem like a workable strategy. 

 

I'm OK with burning actually. The total amount of coins in the system essentially defines its maximum price resolution. Ideally we'd not lose resolution, but it's less important than having a system that does actually work. Moreover, this sort of system is like double spending defence itself - if it does work, it doesn't need to actually be done very frequently because people know the safeguards work and don't try. So in practice total loss of resolution should be limited.

 

Right. It's indeed an assumption that block rewards matter to miners, even the ones that have double spend revenues.