Interesting. I had a very different experience. Double major, working in two labs simultaneously, active member of local ACM, interned with local startup during the school year, volunteered at a local soup kitchen. All that together was about 50 hours/week. Academics (including homework, studying, etc) was only 25 hrs/week on average. But I was very fortunate to have the advantage of not needing to work, which gave me the freedom to scale back my hours on a particularly busy week.

I learned a lot from my CS classes, but I actually felt like most of the value from the degree came from overhearing random chitchat between professors or other students and the reading more about those ideas and experimenting with them in my free time.