Ideas _are_ the patentable work though. The system is designed to get people to share their ideas. The problem is that most patents should never have been granted in the first place, because they are obvious or non-novel.
If you had to manufacture something before you could patent it, then your idea could be stolen by any potential investor. And some solutions you can't manufacture without help from entrenched businesses. Robert Kearns shopped around an idea to GM and Ford for a new wiper system. They stole it without paying him. If patents couldn't be held by NPEs, then the law would always be on GM and Ford's side, because Kearns didn't happen to own a massive automobile production line.
Why should owning a massive car factory be the only thing that qualifies you as an inventor?
Also, anyone who can beat you to market has a defense against your patent claim. The biggest, richest, fastest manufacturers win the right to produce everything they never invented.
Don't get me wrong, the patent system is definitely broken. The way it's broken happens to get exploited by certain non-practicing entities. But the problem isn't NPEs, it's _some_ NPEs, and really, it's just the features of the system those NPEs are exploiting.
The problem with our patent system is that no one actually seems to care about novelty or obviousness, even though they are supposed to.
Consider "a method for thermal refreshment of bread" (patent number 6080436). It's a toaster patented in the year 2000. David Martin, a patent quality assessor, claims that about 30% of the patents his firm reviews are for things that have already been invented.[1]
Software has it's own special version of this problem. Juries can't code, so they don't have any clue what's obvious, what's just an incremental improvement that anyone could produce if they knew the language. Juries can't tell the difference between design tweaks and brand new methods.
The problem is not that the system rewards intellectual effort, the problem is that the system rewards things that are effortless.
[1] http://www.thisamericanlife.org/radio-archives/episode/441/t...