I just disregard the whole "registry" thing and give what I want to give... usually a quilt. I thought it was bad enough being expected to buy a shower gift AND a wedding gift... but to pay for the honeymoon too? Sheesh!
When my daughter got married we gave her $6K to do whatever she wanted, and anything beyond that was on them. It was all we could do. They didn't have money left over to do a honeymoon like they wanted, so they didn't have one.
When a couple has already been living together for a number of years, I just feel so unmotivated to even celebrate their wedding. It's anti-climactic. They have their household set up, and they have already been living as husband and wife, so what are we celebrating? That they are finally doing what they should have done years before? Not judging them, it's just how I feel... I think if they have already been living together, they should go get married discreetly at a justice of the peace. To have a big wedding at that point seems so ridiculous to me. Literally putting the horse BEHIND the cart. I don't usually go to weddings like that, because it's just no fun. I can't get into it. And then everyone thinks I'm judgemental. But to me, a big wedding after living together is disingenuous.
Same for "repeating vows" after 25 or whatever years... If it's done privately and just between the two parties involved, it can be meaningful, I guess. But to put on a big wedding and invite guests and try to do all that would be done in a first wedding just seems like a charade. I often want to ask "Why?" "Didn't you mean your vows the first time?"