Remember in the cartoons its always " eat at joes" why is this? Was it a real place??? is it still there???
Search, search, search.
http://boards.straightdope.com/sdmb/showthread.php?s=&threadid=83086&highlight=cartoon*
Ahh, one of my first threads!
Hey! The title is all capitalized, I guess the only started disallowing the recently.
I can’t give you anything but an opinion. I would think that the appearance of sandwich boards would be the origin of the “eat at xxxx” thingy.
It was then probably picked up in newpaper cartoons, early comic strips, and finally movies. You used a “generic” name rather than a real place. Thus “Joe’s.”
Maybe “Sloppy Joe’s” , another cartoon version I’ve seen.
Sloppy Joe’s is a joint in Key West where Ernest Hemmingway ysed to hang out.
He, Thanks for finding that Muad’Dib, That Thread was also one of my first thread killers, with lots of hunting for the earliest dates.
And my conclusion, even after finding likely candidates:
I should add that it is one of my first threads after I ended a year of lurking.
Surprise!! there is a “Joe’s,” in Redondo Beach, CA 90277, at the northeast corner of Pacific Coast Highway and Carnelian Street. It’s been there at least since the mid-60s. I know, because I saw it when I started attending Redondo Union High School, which is one block to the south. I still eat at Joe’s myself, too. 
Surprise! not!
You have not checked the linked early thread where I posted:
Which means your restaurant is late by 30 years or so.
Hey, I don’t know when the Redondo Beach Joe’s was founded… 
Mmmm…“Eat at Joe’s”…
Haven’t eaten there in quite a while, actually, but I remember it was pretty good.
I have eaten at Joe’s in Santa Barbara MANY times, great place!
There’s a Joe’s Pizza here in Schenectady, but they have a much better slogan than “Eat at Joe’s”:
“Watch your pizza being made by imported hands.”