I can't argue that Season Passes are generally-speaking a bad deal and consumers ought to be wary of them, but I don't think that publishers should stop offering them. Pre-selling DLC ensures that the publishers don't get on the developers asses about releasing the DLC sooner since statistically, DLC sells best right after release (source: http://www.joystiq.com/2010/08/16/eedar-consumers-have-greater-interest-in-dlc-a-month-after-game/ ). This is why on-disc DLC was such a common practice. With Season Passes, the publishers get to maximize DLC sales and the publishers get to take their time and do their DLC right.
That said, everything Jim says still holds more-or-less true. When you buy a Season Pass, you're assuming that you're going to want to buy every ounce of DLC released for that game and you're trusting that the developers and the publishers are going to deliver in a timely manner. And unlike something akin to a pre-order or a Kickstarter pledge, your Season Pass doesn't typically guarantee anything specific. From a consumer standpoint, this is almost never a good deal for you.
I just accept this particular extortion as a necessary evil. I generally like DLC as a concept and in order for DLC to be deemed a worthy investment to most AAA publishers, they have to find a way to cash in on it quickly. They tried on-disc DLC and this led to both underwhelming DLC and pissed-off consumers. So now they're trying to have it both ways. To their credit, I can't really see a better way for them to do it. Yes, they could just make good DLC and sell it piece-mail, but again, statistically their audience will have decreased dramatically as they focused their attention on newer, fresher games.
So long as publishers don't FORCE us to buy Season Passes in order to get certain DLC, I'll just see it as an idiot tax so the developers can take their time to make decent DLC for me to buy later on.