Sealed with a String

Whats the story with 'Shaguns' anyway? As tradition goes, when someone throws a party (at least when its formal enough) - everyone gives them crisp new currency notes wrapped casually in glistening envelopes - sealed with a delicate string.
Is it a way of saying we're practical enough to understand everyone's taste is different, or that we're not bothered enough to actually buy a present?
I was faced with such a situation recently. My friend threw a formal party in celebration of the birth of her baby boy (I wonder if it would've occured, had it been a girl) - and I was faced with the choice of the good old Shagun or perhaps an exciting gift. After all, the market for unique goods for children is wider than teenagers, adults and aged people combined.
However, over a discussion with other invited guests, I realized its best to go with the flow and seek the assistance of the 'practical' money gift.
After all, its not about the way I think - its more about what the recepient considers worthy. And money finds its worth one way or the other, at least that brings solace to my confused mind...