i cant speak about this shop in particular or any of their policies... but it is not completely uncommon for somebody to buy a gun and have no clue what it is the next time they come in to a shop. i sold a gun to a new licensee, went over everything with him- including the kinds of ammo he could use, cleaning kits, etc.
this customer came in the next week when i was not in, he told another employee the wrong information... because of this he bought the wrong ammo, the wrong cleaning kit, and the wrong holster (he did not bring the gun with him, either)
we got him all squared away but to this day he calls mags "clips" and thinks his gun is a "smith and westin". sometimes people just cannot retain new information, since the gun community is expanding so rapidly it is not completely impossible that people are clueless. it's like when somebody knows the make of their car but not the model, year, what size engine, etc. so just keep in mind that not everyone is as into guns, as brilliant, or as awesome as people on this forum.