"tabac" feels too restrictive, "Épicerie" feels more like selling fruits/vegetables, "commerce de proximité" feels like it could include things like a supermarket too.
I can think of more unsavory/xenophobic/slang terms for it, but droguerie seems more appropriate.
And on the other end for someone who never been to Québec, "Je vais au dépanneur" sounds like "I'm going to the mechanics (to fix my car)". Very creative.
Le mot dépanneur peut désigner :
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au Québec, une petite épicerie de proximité ou une supérette.
en Suisse romande, une petite épicerie ouverte les soirs ou les week-ends.
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