Envision Home 432700 Fridge Bin Liners, 3 Count, 12-Inch by 24-Inch, White

do they move around on the fridge shelf if we take out things?

How many sets of these do you need to buy to do the whole fridge?

Are they completely white or do they have the little designs on them?

S&T why not make sizes for the actual fridge shelves also? No 6 packs for veggie design available! Why not?