At the end of the day,running is meant to be a serious competitive sport. Just because-unlike most other competitive sports,where you can only compete against those of a similar standard to yourself-I can line up behind sub-30 10k or sub-65 Half Marathon runners,does not mean I am as worthy of a prize as they are.
The level of dedication and intensity of training put in by the elites is WAY beyond 99% of us.
That doesn't mean that anyone should "give up and go home".Sharing in the race experience and challenging your own PB's is reward in itself,but the prizes should be reserved for the winners.