Exactly, there's a big difference between pro bono and paid work. And trust me, the people you do free work for will expect A LOT MORE from you.

I would say the exceptions would be: a) it's a charity or a cause that you like, or b) you really need to improve a particular skill and it's more of an internship you're looking for.

Either way though, I give you mad props for initiative.

he says after a few months.

I generally agree with your parent that he ought to spend that time doing something that can showcase his skills and increase his chance to get hired. He can gain more exposure working on something in the open (a personal project, an OSS project) than doing some work for a single company.