I have a gluten allergy and I thought this would be more offensive but it's actually pretty funny. I used to work as a clerk at a grocery store and yes, some older people will like be insanely touchy about certain things. Like, I get asking about certain things, but I've not met one person who touched gluten and had a reaction, just as long as it's not in the mouth. Some people get really antsy lol.
I think the real seller here is like, you feel bad for this guy like he's a sad sight capturing that lonely old dying man vibe, but at the same time it's like you can't help but laugh at his ignorance when you suddenly notice the tiny detail written on the vasoline, "gluten free". Some people just need caretakers but don't realize how much of their mind is lost. It sucks but yeah some people worry too much. Anxiety's a terrible thing.
Anywho nice toon lol.