I think it’s a bit of both and the delivery is important. Charging people to attend is bush league. But there’s an implicit understanding that if you attend you at least pay for your plate.
Today’s day and age it’s basically $250 a person. That’s not just your meal being paid for; you’re in effect paying for your share of the celebratory event for the couple getting married. That’s a gift. If it’s close family you obviously do more.
The shit I don’t like is the no kids notices. If you’re inviting me, you know I have kids, either invite us all, or don’t. If I don’t want to bring my kids, that’s my choice, not yours.