I hated mustard and never understood why every burger chain put it on as a matter of course, so the Works bar was my saviour. (They also had one of the first salad bars I ever saw, back when they weren't nearly as common.)
Looking back I can still remember thinking Burger Chef's burgers tasted a little funny...I suspect they were flame-broiled a la Burger King, and that always tasted weird to me. But they had Fun Meals even before McDonald's had Happy Meals, and they got REALLY into "Star Wars" and had a ton of movie-related toys. (Also, Monster Fun Records -- who remembers these?)
Here's an ad teaching Americans of the 1970s how to use the Works bar. Incrediburgible!