If difficulty never increases, sure. If block rewards never change, sure. But both of these things happen and miners most likely to find blocks in the near term (when difficulty is lower and block reward is higher) would benefit most.
How do you figure? The miners most likely to find blocks are also the miners most likely to submit shares that don't find blocks. It's perfectly fair to everyone, all it does is let each miner choose precisely how much variance they want. PPS is fair to everyone. Solo mining is fair to everyone. Everything in-between is fair to everyone -- the difference is just variance.