
I've bought dog hot dogs from the pet supermarket before which have had all the ingredients listed but not supermarket ones as the ingredients tend not to be very specific - just had a quick Google and
this link says that hot dogs can contain herbs and seasonings including garlic, pepper, ground mustard, nutmeg, salt, and onion.
Need to check the ingredients carefully and avoid any that list "herbs and seasonings" then! Maybe that's what she was talking about.