This attitude is self defeating.
The taxpayer money has been spent, and the best (and only) way to recover it is for GM and Chrysler to be successful. A profitable GM will be able to service its outstanding TARP loans, and provide a stock value which will repay the government. Refusing to buy GM cars, while emotionally satisfying, only works against GM's success, and the repayment of the taxpayer loans.
As for the UAW, it is true they fought hard and were successful in the past at winning extremely generous benefits for their employees. But it was the automaker's management which was a negotiating partner, and didn't have the fortitude to keep things more reasonable, even if it meant strikes and nasty public relations. The UAW was doing it's job, fighting for its members. Expecting otherwise is like expecting the wolf to go easy on the sheep.
But with the collapse of the domestic business, and bankruptcy of 2 of the 3 UAW automakers, the UAW woke up in a hurry. The UAW leadership, under Ron Gettlefinger, pushed hard on the rank and file to agree to multiple rounds of contract renegotiations.
If the Detroit 3 can't survive going forward, it is not because the UAW workers are being overpaid. From here on out, "it's the product, stupid".