Expansions didn't get released as often because they're not as cost-effective as DLC. Some games did get a crapload, even before DLC, however. The original The Sims game has a total of seven expansion packs, and the last one was released in 2003. A lot of successful games had two expansion packs. Expansions cost $10 less than core games, so if a game cost $30, it would cost $70 with two expansions. That's better than $60 + whatever the cost of DLC is, but you aren't force-fed stuff you never plan to use.