I think it is important to get a little more info on who made the comment. you mentioned it was the "dealer". Do you mean the owner of the company?
could this person have been a certified mechanic or simply a minimum wage place holder behind a parts counter?
was this person considered experienced expert or just a warm body taking up space and commenting outside their skill set?
hard to know without a little more info.
My dealership is considered on the larger side also has fuel pumps. I know simple questions like is your diesel pumps carrying #1 or #2, what amount of bio is currently in the tanks, what types of additives are being added over and above base product from the refinery is being ordered/added is often returned with blank stares.
So know who was asked and what type of follow up questions is important to determine whether the answer is a flippant or maybe uneducated response or maybe from someone who just wasn't having a good day.
cheers