Imagine a time when four-wheel-drive trucks were sold for their ability to slog through snow and mud, not their ability to repel urban criminals and perform minivan tasks without minivan stigma.
I'm surprised they're advertising mileage. We had a 2-door 258 1983 Cherokee (last year for the big Cherokee) and it never really got 20 mpg, even when we yanked the awful automatic choke. I'd say 15-17 is average...the 5-spd manual might have done better, but we had a 4-spd. It was almost the slowest thing on the road, but off-road it was fun.
The replacement, a 5-spd Ford Explorer, easily got 22-23 highway.