I think it's a cultural thing - and everyone is not going to agree. I personally cannot image going to a wedding and not covering my plate because I grew up with that mentality and my big extended family grew up with that mentality. I attend a lot of weddings and the last one was for a good friend of mine at a nice country club, I gave $150 and that was the norm in my circle.
Everyone has different backgrounds and different norms. Just as you(general) can't imagine paying that much to attend a wedding I(me only) can't imagine paying less, it would make me uncomfortable. Weddings are awesome and amazing things to celebrate and my friend definitely didn't have a spreadsheet out ticking off who paid "enough" and who didn't, to me it's part of the social contract I have with my family and group of friends in my region.
The bolded wording bugs me, because people shouldn't be "paying to attend a wedding." Yes, we spend money to attend -- for a gift, clothes, travel, hotel (if needed). But weddings shouldn't have a cover charge -- implied via CYP or (horrors!) assessed ahead of time. This is not what hosting is about.
WillyNilly, I think it is a lovely gesture for a guest to decide to give a generous monetary gift with the intention of helping the couple offset the cost of putting on the wedding/reception. But as you have stated, that is a call for the guests to make, not the hosts. And snubbing or berating guests after the fact for not covering their plates is the height of boorishness, IMO.
What if there
is no reception? What if the bride and groom elope, or have a private ceremony at city hall? What if there is a reception but I can't attend? If I love the HC, I would still want to give them a gift to wish them well and help them start their new life together. Should I not do that because they didn't spend any money on me?
Bottom line: If you're hosting, you host the event you can afford, whether that's punch and cake, potluck, or a seven-course meal at the country club with the Manhattan String Quartet playing. If you're a guest, you give the gift you can afford and feel moved to give, whether that's a $10 kitchen utensil, a $20 gift card or a big fat check. And if the hosts have stayed within their budget and not overextended themselves with the expectation that they'll be reimbursed by the gifts, then what they *do* get is gravy.