Alongside those items that most married couples only have one of (toasters, bits of crockery etc) the Guardian suggests that big sellers are likely to be "non-iron shirts, large plasma screen TVs and computer games". We suggest that receiving such gifts from your family might confirm you're a hopeless twonk, who can't look after themself and with little prospect of a fulfilling social life to look forward to. Not the best start to unwedded bliss.
We'd much rather splash our cash on a night out, consoling, commiserating or celebrating - whichever's appropriate - as we would for our unmarried friends whose relationships don't work out. Presents when you get married and then more when you split up? What a terrible idea.