I have an idea. If the patents were created to protect inventors, why just not forbid of any sale of patents to the third parties. The patent cannot be sold or inherited period.
What if I'm really just an inventor type, and I don't have any of the skills or the desire necessary to go about making money off my patent. I imagine negotiating with Google, Microsoft, Apple, etc. isn't a simple make a phone call and start receiving checks type process. Not allowing an inventor to sell his patent limits seriously limits a major avenue of revenue for the inventor.
They weren't, they were created to get inventors to disclose their inventions to the public so inventors wouldn't take their trade secrets to the grave with them.
Giving inventors a limited monopoly was the means to that end; why else would they disclose their secrets?