Look at it objectively: two people have to be able to make a profit off of you in this arrangement (the owner and their realtor) and both of those margins will be pretty fat since neither of them is a long-term employee of the other, like you'd see in an apartment complex with an on-site manager.
Real estate agents are always on the landowner's side. Just accept this and the whole system will make more sense (this goes for buying or selling a house too).