Earlier quoted context omitted.
I don't like invoking the word 'rent-seeking' because it's highly subjective. The formal definition is extracting value without providing any. One could easily make the argument that all business investors are like this. Why act like it's just a case of a few people then?
I don't think it's just a case of a few people. Rent-seeking by itself is morally neutral, like guns. Like a gun, it's how you use it that determines if you're contributing positive value to overall society. The purpose of the economy is also not the accumulation of wealth by a few people. Having lots of money is nice but it turns out it's nowhere near the most important thing in life.
This strikes me as a bad analogy. What differentiates your statement from
Theft by itself is morally neutral, [...] it's what you steal that determines if you're contributing positive value to overall society.
You might be willing to endorse that statement, but I think most people would not.
I think that if you want to assert that rent-seeking is tool-like, with multiple uses some positive and some negative, then the burden of proof is on you to provide some examples.