I would say greed is at least part of the problem as I see accounts every day that chose to only take. Still, I have opted to delegate over half my SP to others to vote as they wish. I have picked some I trust to distribute it well and I don't mind if they use some on themselves. I can always take it back once they have built up their accounts.
I have wondered if I could handle the responsibility of votes worth tens of dollars. I think mine was worth at least $2 at one point.
I do think that spreading the voting power across more accounts would improve matters as there would be less massive votes, but when the vote sellers pay for delegation then some will take that rather than having to do any voting themselves.
There's a lot of Steem that isn't doing any voting in exchanges and certain whales who don't use it.
There's no single answer, but it's good to have these discussions to see other options.