Proof of payment does not equal receipt. Kalahari use the same system as do most companies, generally you don't notice this in an online order with home delivery. Nobody releases goods without payment, its bad business and its easy to forge a proof of payment, any business doing that will be filling for liquidation by year-end.
Like I said you don't notice this gap because most online retailers bring in the stock when they get proof of payment and then sent it off to the customer when payment clears. That gap is not noticeable because the customer just assumes it a delivery thing. If your gonna pay via an EFT and then pick it up in store your gonna have a bad time waiting for it to clear before pick up.
Why do you think Takealot says on their pre-orders to send payment in prior to release?
Granted your reply might have been very arrogant but I'm sure he gets the same e-mail every day from people who don't understand banking clearance.