This is counter to my experience. I was able to work part-time jobs just fine, and having that experience made me a much more competitive candidate upon graduation.
I would still have worked most if not all of my summers, but never more than 5 hours a week during the semesters. My job, which I actually really liked, demanded 20, which also required another 6-10 hours commuting on top of 5-8 hours of commuting to school.
I had also worked in tech for a year before starting school, so I was a bit less worried about having experience to list. And in the end it didn't matter because I started a company and ran that for 5 years instead.
You definitely can't pay for everything on 10 hours a week, but it at least pays the bar tab...