I don't think it's what people believe. But I think it's what people prefer to believe rather than have the knowledge that Lawrie is actually so dumb that he would think a runner scoring in that situation would make any difference. Again to clarify, there are only 2 possibilities:
1) Brett Lawrie is so selfish he wanted Lind to score in that situation so he could have an RBI
2) Brett Lawrie is so dumb he thought a runner scoring from third in the 9th down by more than 1 run would actually make a difference on the outcome of the game
Both of these possibilities are awfully disturbing, hence Lawrie's popularity going down the drain lately.