People in the UK probably call it something different.
Like suspenders in the US is what the guy keeps his trousers up with but in the UK it holds up the girls fancy tights, which is kind of what the garter does...but it is really just ceremonial and tradition..at least the one that gets pulled off and tossed to the crowd.
go here to see for yourself.
And its the guy that pulls it off the girls leg and tosses it to the single blokes at the party. That guy then gives it a good sniff and acts silly with it. He then dances with the girl that catches the brides flower bouquet.
in fact she got floor tickets to DC (Sept 29th) for my birthday, which is 7 hours from where we live.. great trip, stayed at a nice hotel, walked to the venue, had a great time, and I grabbed Morrissey's hand.. such a loving wife