[toast0]

It's not just paying the person to get your product after you pay for it; they also need to rearrange their space to store those things (many which are bulky) towards the front of the store. Locked cases are an in between step, need a person to help, but don't need a dedicated space at the front.

[kergonath]

Fair enough, this needs to be taken into account in the stock management.

That said, for bulky items there is either someone bringing them over, or a counter closer to where the stuff is stored (often in another building). They don't keep stuff like piles of large TVs at the front of the store.