Craig, cutting open fuel supply lines and primer bulbs and parading them in front of customers is almost every shops favorite thing to do.
Fact is: regardless of the "EPA rated permeation value" stamped on the hose, it is gonna look like that after 6-7 years. LOL
Everyone is all about their water pump impellers....but nobody ever gives their fuel lines and Oil injection hoses a thought until one of them starts leaking.
They need replacing routinely also. All of them.