Do any of you freelance?

What are your thoughts on the term of Net15? Ever encounter a freelance employer that will pay you up front within15 days of your first invoice?
or are you forever doomed to having to wait 30 days before they pay you (after your invoice FFS at the end of the month)…hence Net 60.
I mean…from my stand point, ive worked manual labour jobs keen on hiring at the minimum wage, and they will page you literally 15 days after and this is NOT freelance.
so anything from Mcdonalds to shitty shipping work…they will pay you like literally in the next pay period of biweekly.
But seemingly for freelance on work that is completely different and pay that is a few bucks more per hour, they will take a goddamn month to pay up. ffs