There a couple of points that I either don't understand or people seem to be missing or I'm missing:
1) No one has to buy any DLC AND you can pick and chose the one or ones you buy. In my case, I ended up waiting a little while and bought them for less when STEAM bundle them because I didn't have to have them immediately.
2) Fortunately, I'm not on a budget, so I can purchase what I want especially when it comes to computer games. So I do have the luxury of being able to buy just about anything I want to buy when it comes to expansions or DLCs. However, I haven't brought all the DLCs, just the ones that interest me. Anyone can do that. The company will track who sells and what doesn't and tailor future releases to what sells.
3) Given that a DLC cost about what a cup of Starbucks cost, all the DLCs together cost a heck of lot less that what it cost to take my wife and myself to a movie - if I get more than 90 minutes worth of play time from one either via discussion on this forum via comments from me (which usually aren't too bright) or reading some insightful comments from you or play time, I'm way ahead of the game as far as getting good value for buck. And at the end of the day, that's what counts.
4) Would I buy an expansion? It depends on what's in it. I would guess yes but I would, most likely, wait and see what kind of comments I would see about it first.
In any case, if you feel the DLCs are overpriced, don't purchase it. I don't purchase ones that I don't have an interest in. Having managed programmers (not for gaming but other stuff), I can guarantee it takes more than five minutes to produce this stuff and they're not becoming millionaires off selling DLCs.
But I do know that the DLCs I purchase represent a good value for me - I get more than an hour and half of entertainment out of each of them, and at $5 or so, that the cheapest entertainment that I get anywhere these days. And that the way I judge purchases of computer games - do I get enough entertainment value out of the money I put out? If yes, its a good purchase. If no, then its a bad purchase. And its ranked against all my other entertainment purchases.
And as a note, if I didn't enjoy the core game, as someone noted, then I wouldn't even consider purchasing a DLC.