CLueless adolescent staff, mainly
You go in, you see the toaster (other appliances are available) you like, you use your phone to check any details and you take it to the till and the (in our experience) pleasant staff let you pay for it.
I don't go there for Nobel prize winning philosophy
What if no phone..?
Use Mrs K's phone
or just don't buy it. The routing usually consists of her pointing at something saying 'I want', I put up a pathetically failing defence of 'but we've already got one' and then I go look at the reviews of it at Amazon. If they don't say it's crap then out comes my credit card.
To be fair last thing bought there was our printer and before that a toaster. All the recent expensive stuff came with the dead relative funded new kitchen.