Corrected entry: When Max and Paddy go to France on the "booze run", the place they go to is called "Le Grande Marche". There isn't an "E" at the end of grand if it is masculine.
Corrected entry: When we see two of the characters in a French warehouse, one of them picks up 'Les Cadbury's Fingres' (another reference to Peter Kay's stand-up jokes). The problem is that 'Fingres' is not French for fingers. In fact it is even close.
Correction: "Les Cadburys Fingres" is derived from Peter Kay's previous stand up joke where he laughs at the way British people take notice of their food proucts translated in a foreign country. He says, "Les Cadburys Fingres" off the cuff and quicky states that he doesn't know French and so the blatant wrong-ness of the translation is deliberate.
Correction: A mistake yes, but not a film mistake. The place is real; it's a booze barn in Calais. The owners are English and thought (probably correctly) that 'Le Grande Marche' looks more French than 'Le Grand Marche', and would appeal to their largely British clientele.