Garden gnomes were originally put in gardens because they were (jokingly I'm sure) considered to come to life at night and do the gardening for you. Garden Owners would move them around each day as if the gnomes had been hard at work trimming little hedges and helping out wildlife.
Now days garden gnomes have taken on a sort of cultural relevence. People tend to either *love* them or be completely indifferent. You can even find garden gnomes sporting jet-packs nowdays. I can't post links but gardengnomeworld dot com/Liutenant-Sweeney-Salvatone-Rocket-Gnome is a good example of how they've evolved.
Plus, Gnomeo and Juliet is about to come out so you could say overall interest is at an all time high.
Hurray for gnomes. If only they'd do my paperwork now... =/