Do We Really Need The On Line Travel Agencies?

Christopher Elliott is what we would call a “travel ombudsman”. He has a regular column in USA Today and writes frequently for the National Geographic Traveler. He also has a web site where people can take complaints relating to the travel industry.
After spending some time on his web site, I found myself wondering why any of us use what’s known in the trade as an “on-line travel agency”, meaning booking sites like Expedia or Travelocity or Hotels-dot-com. A lot of the complaints he gets involve web sites like those and they’re basically the same: when something goes wrong and a traveler complains, the hotel says it’s the travel agency’s fault; the agency says the blame goes to the hotel. 
So what’s the point of using the middlemen? The original concept was that the web site would sort through the options and find the cheapest rate or fare. But that’s almost never what happens anymore. If Kayak shows American Airlines has a $380 fare from Maui to L.A., I check that flight on American’s web site and the fare will be the same.
That’s almost always true of hotel rates, too. But—and it’s a significant but—if you book direct from the hotel’s web site, your internet connection comes at no charge. Book through one of those other web sites and the wifi will cost you $12.95 a day.
One other thing—and I got this from a friend of mine who is the general manager of a hotel here on Maui—book through an on-line travel agency and chances are you’ll get a somewhat inferior room. Reason? The hotel paid a commission for your booking, which means they make less money on the room you’ll be occupying. That’s why you end up in one of the rooms that is awaiting renovation, or is farthest from the elevators, or looks out over the delivery dock and the dumpsters. Or all three.
So what’s the point in using one of those sites? I now use them to compare hotels for rates, location and amenities … then, after picking the one I want, I go to that hotel’s web site to book the room? I’ll probably get the same rate, plus the wi-fi will be free and I’ll be more likely to get a better room. But that just seems too obvious. What am I missing?