They are not just learning from the company; they are also giving their precious time to the company’s work

I like the fact you said interns are learning, but then you added they are giving their precious time to the company so they need to get paid is wrong..

Student go to school to learn, they waste transport, pay for accomodations, buy textbook and also give their precious time to the school, will the school also pay them?

The similarity between schooling and internship is learning!