In practice if an apartment makes money by way of this "kickback" it also offsets the rent that they have to charge the tenants of that building. Similar to airlines, assuming that if one charge is reduced or eliminated it won't show up in another area (baggage fees) or in the case of a building reduced maintenance or services doesn't take into account how real businesses operate. There is nothing wrong with a business making money and in fact a business that is profitable is also good for it's customers. A business that loses money is not. The "peanut gallery" (people who write blog posts and comment on this but don't actually even own their own business) aren't in a good position to know all the ins and outs.
That said, sure some businesses rip people off (if you want to call it that) but don't assume that is the default case.
Edit: Perhaps this attorney (at Harvard no less) could write an article about the 'legal tax' on society as a result of lack of competition in the legal market. The cost to consumers for that (since it's passed along in product costs) is almost certainly way greater than whatever the 'vig' is for higher priced cable television or internet service.