I'm not disagreeing with you; I think I agree with your basis idea that businesses shouldn't get a R&D free ride at taxpayer expense, but your comments raise some questions.
If the business risk to researching and developing some new drug or technology is very high with the chance of success and profit very low, do you think a business will take on that risk? That's why the government which, for better off for worse, has no target profit in mind takes on high-risk research that may eventually yield success and benefit the public. GPS is an example of this. Do you think that any commercial entity would have had the resources to develop this technology?
Second question, feeding off the first: If a new technology/drug/etc is developed by the government, who else is going to commercialize it for the benefit of the public?