Only the first time visits (when you dont know history) was a dewormer ever given to our gang. Skinny was given it at his fist appt. Eleanor had it done through PetSmart adoption. Pretty sure Thumper did to since we got her through PetSmart Adoption. It's pretty much routine with shelter that processes them to go to PetSmart.

Unless there has been a history of worms, I have not known it to be done all the time.