in the beginning developers were paying it with their own free time
many still do now, many run relays for free, do all sorts of things for free, because that's humanity, that's how the wonderful universe of open-source software was created in the past 20 years
but opensats and hrf and others have put money on the table too, is there an issue with that?
I agree that having everything funded by grants distorts incentives and ends up attracting some wrong people
but having real corporations running clients for profit is much worse