I've bought the LA Noire Season Pass for $3 or $4.
Sleeping Dogs DLC packs for $3 altogether.
Max Payne 3 Season Pass with game for $7.
Darksiders 2 Season Pass for $3.
Trials Fusion Season Pass for $6.
RDR complete game and DLC for $8.
There's other but you get the idea. I never pay full price for DLC. I plan to pick up Rocket League DLC eventually at full price. I think that's the only game where I have no problems paying full price.
I've almost certainly spent over £2000 on Madden over the past ~6 years. I've stopped playing Ultimate Team now, though, so haven't spent a penny on it this year (and probably never will in the future).
Other than that, About £40 worth of Silver in Destiny is my next chunk.
Well, are we talking reasonable story DLCs like say Fallout 3/NV/Witcher/etc or BS stuff? If the former I have bought for quite a lot of games like the ones mentioned above, Bioshock, Deus Ex HR, etc.. And for the latter I wasted like $25 on NBA 2K15 card game for some reason.
For sure $100-200 for more Rockband songs. It's actually become a detriment to the series. Since I made a Xbox 360 -> PS4 jump, I can't get transfer my DLC to Rockband 4. As a result, I can't bring myself to buy Rockband 4.
I love Harmonix so it makes me feel a little bad. I'll buy Amplitude to even it out.
One of my favorite things to do in games is character customization and decorating. PlayStation Home was basically customization simulator. Every week there were new houses, new decorations, new furniture, new clothes. Then they added dances, vehicles, other random crap.
I also used PlayStation Home regularly with a lot of friends after school so I always felt like I was getting my moneys worth. Everything was getting used at some point, and this happened for 7 years. PlayStation Home is long gone now and the crazy thing is that I don't regret any of it.