My sister did a honeymoon fund, but that's all she did. And it was itemized, like, "night at hotel" "such and such excursion," "dinner at XYZ restaurant." Our mom thought it was tacky, and other people in the family were pissed she didn't do a traditional registry, but I thought it was kind of cool. They didn't want or need registry things, and had a pretty cool honeymoon. I think it would have crossed over into tacky if she had a bunch of other stuff attached, like this person.