GPL (and others) allow such a model as well. There is nothing in the GPL preventing me from selling for as much as I like. The buyer however has to receive the source code (upon request) and can share it for free (as in beer) if they like.
https://opensource.org/osd.html
As a result, the license would be incompatible with copyleft licenses.
Of course, you could kindly ask your "customers" to please pay for a license in case they're using the software for some purpose. Good Luck with that.