mmm, not necessarily. If you were interested in a specific field you could visit the class a few times and sit in, observe, ask questions of the professor or aids on office time. If you want to do a lot of things at a university, you can likely make it happen.

In theory yes, it practice, it was hard. I mean, I got into a lab, but it was a hard struggle to do so, with univ. system working against me (most of the time) rather than in favour.

IMHO its mainly the difference between top-down organization (where student is expected to perform assigned task, here: attend classes) rather than bottom-up (where the environment offers opportunities, which can be used).

If you had a very different experience, just curious - which country/univ.?