If I'm enjoying my time when I play games, then I don't feel bad, but if it feels like I'm just doing it to pass time, then yeah I feel a bit guilty. I feel like I'm not imaginative enough (or I'm just plain lazy) to come up with something more constructive to do with my time, so I just fall into what is the norm for me.

Even when I play games all day and feel bad about it, it doesn't bother me nearly as much as when/if I slept the entire day. That's when I really feel guilty.