I'm not going to knock it, I worked damn hard while I was at college/university, both studywise and with my job.. however..
If you are at college, 40+ hours a week (when I was, I was in class/labs 9-5 every day, and of course, had lab reports to write etc). I always wondered, why the expectation is there by many parents that you should then go out and get a job on top of that. I know part-time jobs aren't exactly taxing and yes give you more money coming in. But still.. how many parents go out, work a full week, and then, have a part time job ontop? very few I would expect... the rest will be 'hell no, I've already been up all day'