They'll put essentials in the back so you have to walk through the entire store to get to them, and place pricier items at eye level so you're more likely to grab them.
Plus, grocery stores tend to charge more for certain products than others, even if you aren't getting more value. Next time you're shopping, think twice before tossing these pricey items into your cart:
BI Graphics_9 overpriced grocery items to avoid_02