As a student who worked during most of his studies: a low-paying job gives you as much experience and is definitely preferable.

With most of my bosses, I had the following deal: "I have no experience, so every task lasts as long as I think I need. You pay a low wage, so if you hit one of the points where I am actually experienced: you make a good cut. If you assign me to tasks where I have to learn everything: you make a bad cut." It worked great, if you know the line where you shouldn't force those terms.

Its a business and working for free is harmful to everyone who wants to make a living from it.