Same reason we now have trick-or-treat, prom dances for 16-year-olds, caps in the middle of words and... well, you get the idea: the transatlantic influence.
I remember when I was a boy...(etc)
Acca (Acco?) fasteners Page 2
Acco fastners are about 10cm long (ie the spacing of a standard hole punch) and consist of a flat piece of metal with two 10cm projections, one at each end. These poke through the holes and then another flat piece of metal clamps over the top and the two projections from the base fold down onto it to keep it in place and are then slipped under a sliding metal loop on the top piece.
Try Staples the stationary supermarket.