I wouldn't say asking for money only is the way to go but there is a way around this. My best friend is marrying a guy from Europe and they are currently living there. For their engagement party here in the states a note on the invite stated,
"In lieu of gifts the parents of the bride have set up a wishing well for couple"
This way you only get cards (usually filled with money) instead of large packages of things you already have lying around the house.