If you look for the episode where Flanders
opens up a Leftorium, you see lots of
Springfielders who are only lefthanded
(like mr.Burns and Ned himself.) Yet
in other Simpsons-episodes Burns and
al the other "Lefties" are right-handed
(or maybe Ambidexter). Wich means they
didn't have to buy all the stuff in Flanders'
shop!