Or they're real lottery jobs that may effectively require volunteer/low-wage dues paying.
But, in any case, internships that don't pay or pay minimally tend to indicate a field that you probably won't earn a lot in anyway.
There are probably exceptions with some summer jobs where the pay may not be a lot but it looks good on a resume in a field that does pay good salaries.
Although those jobs tend to be low-paying and insecure as well.