Hmm... to address the OP; I think NASA is probably worried about more than just funding. As soon as you start taking money from one group, you have to start modifying your goals to include thier interests. They probably prefer to stay "pure". Just guessing, it's not like I secretly work for NASA...
...yeah, like i said, i don't secretly work for NASA. I sell insurance. And don't flame me with reasons why the above way of thinking is stupid or wrong, i'm not saying i agree or disagree. just offering what thier point of view might be.