The plan wasn't to benefit the poor. The plan was to get larger, less efficient vehicles off the street and replaced with something more efficient that had a smaller carbon foot print.
Most of the people I know who took advantage of the program were upper middle class, who did just as you said. They traded their kids (or their 3rd) gas guzzler for something smaller and cheaper.
As for the people who didn't qualify, I'm not too let down over that. I'm paying for everyone's home foreclosure. The car might put me over the edge.