Actually--its not a bad point. when I vote at the local school there are never police around and a bunch of old ladies manning the election place. It is a target rich environment if you are an Islamofascist.
And other than not having a school building involved, what difference would a different location make? IMO, it would be another sign of caving to terrorism. The next suggestion might be to never have any more than two people within a hundred yards of any other people so a car bomb would have minimal damage.
As we saw in Russia a few weeks back, schools with or without polling places, are a 'target rich' environment.
How much 'security' do you want? Do we need Delta Force at every school every day and every polling place every election? Or are we going to kill these terrorist cockroaches where they breed?