I think that it's hard to develop some kind of overall theory about why people choose the type of limit games they want to play with because I've noticed so much variation in playing at different casinos (and online).
I mean, when I first started out, the local Indian casino had a 8/16 table where all the best poker players played at. This was because there weren't any no-limit tables and 8/16 was the highest limit table there. But when I started playing at Commerce in Los Angeles, the 8/16 table turned out to be full of people who didn't have much of a clue how to play poker.
So I think it totally varies depending on where you play, what type of limit games are available there, what type of crowd the casino draws, etc...there are a lot of factors. But once you play at a certain place for awhile, it's easy to figure out which tables are usually the easiset, and on what days (like the 200 NL table at Commerce on a Friday or Saturday night

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