As Notters says above, people will go back round, choose a different cashier to pay at, couples will split up and do two separate buys etc. I can’t see it helping things as much as they think.
Same at my local Sainsbury’s earlier. First time that every single fruit and veg item has been emptied out since this started. The only person who is going to survive this is that French bloke Mr Mangetout who ate that Cessna. He can just pay for the metal shelving at the self service checkout...