i don’t know what programming era you are from, but i don’t recall a single instance of getting raw source code with software.
that said it is very possible that you and i have trod divergent paths. i was paid to write software for my employer, like many people in those days, so what we did purchase was mostly system utilities, and compliers.
of course that was the days of things like useful help utilities, and vendors who would modify their programs to your specs.
Yeah--these days vendors just want to sell a generic license and move on to the next sale.
Yes--I do realize the above statement is a generalization and not all vendors may fit into that statement. There may be exceptions.