I don't do this but EVERY single time DH and DS1 are in the shops together they come back with at least one toy or book. Today they went to pick up a few bits and came back with goal posts. Yesterday it was a small toy car, the time before that it was a set of construction vehicles, before that a paddling pool...the list goes on.
The worst one was when he came back with a tent. You might be thinking a play tent isn't so bad but it was a real camping tent which DH proceeded to put up in the living room and it was before we moved and the old house was tiny!