Even when the fees are lower then, it would not be a problem when that would mean some miners have to be switched off because they get inefficient. The bitcoin network is 100 times more secure than needed. One would say that this means way way too many miners are attracted by the high rewards that are paid at the moment.
There would be spam from the people that are now against blocksize increase. Just to make a point. But their funds will run out sooner rather than later, so I guess this would hardly be a problem anyway.
I'm still greatly in favor for increasing blocksize, but this discussion has been going on so long, it seems there will never be consensus.
You are right... it's somewhat like a chicken-egg problem. If the blocksize controversy wouldn't exist then no spamming would happen. No one would pay the fees for that useless task.
So the fear of the spam is something evocated at the end.
I think consensus will be found. The matter of fact is that normal bitcoiners are powerless and that miners decide what happens. And it looks like the biggest majority of miners is for raising blocksize limit. It is a good sign since it says they see the risk for bitcoin when nothing happens and they are not greedy enough to consider the "fee market".