Was the StayPuft Marshmallow Man based on a real product mascot, or was it invented just for the movie? I remember Jet Puffed Marshmallows, but I don’t recall a marshmallow man mascot. Where’d he come from?
I just assumed he was made up, possibly based on the Pilsbury Doughboy.
Yep:
One of my favorite movies. Can you tell? 
IIRC, they had an idea for a product placement, but it fell through, so they just made up the name. It might have been inspired by a Canadian product, Ackroyd, being a Canuck and all.
I believe that the original script called for it to be the Pillsbury Doughboy, but Pillsbury did not give permission. They’re pretty protective of the Doughboy.
When the Pillsbury doughboy turned 25, several years after Ghostbusters was released, there was a large(several stories tall) inflatable doughboy outside the building - he looked very much like the Stay Puft marshmellow man.
This StayPuft guy is a sailor, he’s in New York . . . We get this guy laid we got no problem.
When Sigourney Weaver’s character comes back to the apartment with her shopping, just before the eggs fry on the bench and Hell appears in the fridge, you can see she has a pack of Stay-Puft Marshmallows.
Wow, that’s odd – I’d always assumed Stay Puft was a real product, and the Man the real mascot. Am I misremembering some other marshmellow product that had a mascot?
I was at a con in which the winner of the costume display was a guy who’d made up a costume of the marshmallow man. It was perfectly done, made out of sheets of white sponge foam rubber. The head was detachable, and except for displays he kept it off most of the time, because the costume was so hot. That foam was an excellent insulator.
Well, as long as you don’t cross the beams.
The Stay-Puft marshmallow man was real dammit. I distinctly remember toasting them at campfires in the 1950’s. I’ll look for evidence.
Was that at Camp Waconda?
Mother pus-bucket!
Nobody steps on a church in my town!
Hello, sailor. Is that an inflation valve, or are you just glad to see me?