You know, I have often heard people say this, but even 50 years ago when my wife and I married, we paid for our wedding ourselves. Our kids paid for the bulk of their weddings themselves. I've seen on TV where the father of the bride pays for the wedding, but I don't think I know any in real life where that's the case. We chipped in where we could for our kids and in some cases their in laws helped a little too. Maybe the couple paying themselves is the other reason it's considered rude here in the northeast not to cover your plate.
We also paid for our wedding.
But I was asking more for the comment that the guests should pay the cost of their meal. I would NEVER have asked friends and families to do that.
However, if that IS the norm, I will be going to very few weddings, if any.