You don't appear to understand what an "investment" is.
A car is not an investment. A car does not by itself earn you money or increase in value over time. A house, on the other hand, IS an investment because its value increases over time, and you can use it to make money (if you buy it as a rental, of course).
An investment is something that makes the money you put into it grow into more money. A car doesn't do that, but a house/property does.
That is why I do not make payments on a car. It makes no financial sense to make interest payments on something that will keep going down in value. The only thing I will pay interest on is something that will make me money over time (ie, property).
Now, regarding your implication that these bailouts were an investment, that is really irrelevant. The fact is, the federal govt does not have the authority to loan money to companies that are not doing well financially. If they are unable to stay afloat themselves, they should be allowed to fall so that other, more economically viable companies can move in and provide products/services that the public wants.
As for infrastructure (like roads), that is necessary for economic development (which the govt needs in order to collect taxes), so it is justifiable that the govt would provide these basic communal services.