Well, first of all, a wedding gift is not required of guests. Ever. That goes for attending, not attending, wedding next door, wedding in Timbuktu. That doesn’t mean it’s not customary, but according to traditional etiquette, it’s not required–in a similar way that a hostess gift is customary, but not required if you have a dinner party.
To me, it’s not a “gray area” when it comes to destination weddings a) because see above and b) because:
in order to attend a Destination Wedding, I am likely to pay AT LEAST several hundred dollars, if not approaching a thousand. Let’s pick Hawaii as an example, and I’ll be conservative:
Hotel: $100/night – 3 nights, $300
Food: $100/day – 2 days $200
Taxi: $60, both ways to airport
…so that’s about $1000. Would you like to also add in the money that I would be spending back home for things like kenneling the dog? Put another $300 on top of that. And it’s not just about the money. In order to attend a Destination Wedding, I’m probably going to have to take vacation days from work (TRY attaching a monetary value on that). If I had kids, I would also have to arrange for their care, or if they were invited, I coudl take them and tack on MORE cost (and possibly have them miss school).
I’m willing to do this–and have done it as far as Italy and France–for very, very good friends, as your friends are willing to do for you. And otherwise, believe me, I’d much rather give you a $100 santoku or whatever, which is why you got gifts from non-attendees.
But please–don’t go around thinking that it’s somehow bad form for people who generously honored you to spend that much time and effort and yes–money–to forgo a card. It doesn’t matter how wealthy they are (and by the way, it’s pretty tacky (there, I said it) to first assume that you have knowledge or understanding of your friends’ finances and then that your perception gives you the right to presume that they spend whatever their discretionary income is on you–as opposed to say, putting it into their kids’ college fund, or their retirement fund, or going on their own vacation, or getting a new roof, or whatever else is their right to do with it). It also doesn’t matter how much YOU and your Fiance choose to spend on your friends. Either give freely or don’t give at all, but to give with the expectation of a return is bad etiquette. It just is.