I'm not sure where you shop, but while individual items may move a little within an aisle, for the most part all the grocery stores I go to are organized the same basic way and items within certain categories are always in the same place. If some spaz moved things around constantly to waste my time, I'd go shop somewhere else.
Yeah you move around an end-cap display pretty often, but bread is always in the same place. Some creative marketing genius never decides it might sell better next to the tampons.
I guess if your weekly shopping list regularly includes items from women's boutique shops like the Coach store, you might find things shuffled around drastically, but ice cream goes in coolers and coolers are friggin heavy, ergo ice cream will always be in the same aisle.
It would be really handy to have a grocery list in location order for a change.