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.
It's not the norm that couples ask for cash - THAT would be rude. The responsibility for knowing falls on the guest. It's rude to attend if you can't cover your plate and your presence wouldn't really be missed by the couple or perhaps their parents.