Actually yeah, parasitic selfishness should definitely be discouraged in a healthy society
Giving things way to people for less than they are worth may not be good idea, but I don't think I would call that parasitic.
Instead, that is closer to charity.
I would not use the word "parasitic" to describe a situation where good and services are very cheap and good.
It doesn't need to be a false dichotomy between what it is now and stalinist Russia comunism.
Note: the blood suckers is not the whole of the capital market of course, they produce value. The problem is some players and some practices..