I have both sides on that issue.
I remember dd1 and her friends (in year 1) discussing whether it was a good idea to be naughty one day to try and get the star of the day. They decided it wasn't worth it, but it was an interesting discussion. I sat outside ready to go in if the discussion went towards being naughty, but wasn't needed. Star of the day (they could only get in once a week) went consistantly to the 4 children in that class who weren't consistantly good. Occasionally they remembered to give it out on the 5th day as well. 
Dd2 (year 4) still gets frustrated about being rewarded for being "not bad". Dd1 got a lot of awards, so I think she eventually stopped minding, but dd2 seems to be the child who's constantly overlooked at school. She generally achieves similar to dd1, but with less flair, and more fuss, so I think her achievements are often overshadowed by the fuss.
Ds (year 1) is the one who gets the rewards. They've started a point reward system in class, which they can get one every day to get a (small) reward on Friday. His comments on it. "If I get one before break. That's good because I don't need to worry about being good for the rest of the day. If I haven't got one before break, I make bad choices after break. Then I am making good choices after lunch and I'll get my magic point after lunch for not being bad then."
He had had all the school "big" awards since they started awarding them, the only child in his year to have done so. Most haven't achieved more than one.
It is good for him because if he thinks it's in the offing he can be very good. But it does take more effort for him to remember to listen, sit still, not poke the person in front, shout "poo" at an inopportune moment... than it did for the girls.
I feel quite embarrassed when he comes out with another award. I remember how dd1 in particular used to feel it was unfair, and feel for the children who always do what he gets rewards for.
But otoh, if it means that he works better in class, he's not disrupting the other children, or taking up the teacher's time to sort him out, it does mean that the other children get more of the teacher's time. And he is inspired by having an award, so you could argue it's worth it.
I think he gets more awards than most because he can be beautifully behaved, and he can be dreadful. The other children in his form that tend to make "bad choices" I think are more consistant if that makes sense.