From what I've seen, the fuel usage can vary drastically from one Escape to another. Some people with V6's report as low as 12 mpg (5.2 km/l) while other report 24-27 mpg (10-11.5 km/l). Unfortunately, I'm on the lower end of that scale.
With my 2002 V6 Escape, I drive 90%+ city. My last tank was all stop and go around town with short trips around 15 min each. I filled up at 144.3 miles (241 km) and put 10.949 gal (41.446 liters) into the tank. That comes to 13.18 mpg or 5.81 km/l. My mileage is absolutely abysmal in the winter. On a mostly highway trip, I can improve to about 18 mpg or 7.6 km/l. When I first got the car, I admit, I wasn't easy on it but I didn't thrash it either. Now I tend to drive in a much more relaxed fashion. It doesn't help much. As a side note, I lost 2 mpg on average when I replaced my tires 3 years ago with Goodyear Fortera's (Silent Armor, not Triple Tread). When I first got my Escape, I averaged around 18 mpg (7.6 km/l) now I'm closer to 15 mpg (6.4 km/l) overall...