If everyone gives up mining bitcoin will end up centralized.
That would be true,....IF mining wouldn't be centralized pretty much already.
Most of todays "miners" actually aren't miners, they're just hash-sellers, selling their ressources to a pool.
The only real miners are the operators of those pools.
How exactly is mining centralized now? Sure, miners on a pool don't know what block they are working but that doesn't mean a pool of miners can't democratically vote on decisions of a pool by moving to another. If tomorrow BTCGuild plus a few others decided to start pushing 50BTC block rewards people would catch on quick and withdraw their resources from the pool. If we ever had a hard fork I know I'd sure want one or two million people choosing which pool and therefore which chain to mine instead of a few dozen people.
I mine, and I have what I think most true bitcoin newbies would consider quite a bit invested in mining. I still want more people to start mining, because I believe that more individuals (no matter where or how they mine) invested in mining will keep the coin more stable and in the end that is best for all.