Jeeps are limited 3500lbs not by the strength of it's hitch.
It can be a combination of other factors such as wheelbase, lack of certain stability features, inadequate brake system or even the transmission itself (god knows that auto has a hard enough time offroad alone, let alone pulling a trailer) Neither does the V6 lend itself to towing either.
And the JK would fit all of those problem areas to limit towing ability.
The 2-doors are rated even lower due to the instability of the short wheelbase.
I had a Tomkin rear recovery bumper on my YJ that was FAR less substantial then the JK bumpers I see running around, and I used the receiver hitch on that combined with a Warn insert shackle all the time to pull myself out backwards. The bumper had tie ins to the frame, of course, so it worked really well and I never had issues with it breaking, bending or cracking anything by tugging on it, and I imagine the beefier frames and bumpers on the JKs are far more suited to boot.
2011 JK, made the year before we all die, warranty be damned.