well when ur selling things that only cost a buck or so, the small interact fee does indeed cut into your bottom line. The Great Canadian Bagel here locally has now stopped taking it as well because they cant "afford" it
It kinda sucks but it hurts their bottom line and would make lines VERY slow.
Anyway I've recently come to never use debit cards at all. $.50 for some cash is retarded when I can just get a cash advance on my visa card (then all I pay is 10% annual interest which works out to about virtually nothing over even a months period on, say $20 withdrawal) or use a visa card almost anywhere.