Hi duzzer
Really, I am only a dummy with Grump's arm up my back
Seriously, it cannot be worth the agravation and effort to carry round tinned food and drink - both of which will be very heavy and may affect your luggage weight allowance - to save €4 or €5. You will have enough to carry anyway, if you have children with you.
So don't bother.
Lana PS But Grump has never been to a supermarket!