I just start asking them questions about their t-case/axle/crawl ratios, or their low-pinion D30 and why they have a transfer case drop instead of a slip yoke eliminator, or how their toothpick-thin tie rod has managed to hold up to their 35"+ tires. This is usually enough to weed out the bros from the pros.
This summer, some guy with an overbuilt CJ tagged along with our group and kept telling people over the CB "You guys without lockers will want to keep your speed up through here!" on a fairly steep uphill section of loose, medium-sized rocks. I'd done the area about two dozen times in my YJ with open 3.07's before with no problem, so I purposefully crawled as slow as possible in my grocery-getter with its auto and 4.56's (open). Didn't slip a wheel once.
This guy. Nothing against him, I just didn't appreciate the lack of confidence he seemed to have in my lowly unibody XJ. Give me any POS, I can pick a decent line to make it up a lot further than you think the vehicle might be able to.
Almost every CJ/YJ owner I've met is at least an automotive enthusiast of some sort while maybe a good fraction of TJ owners are just weekend warriors. But it makes sense, because TJ's were the first real Wranglers to incorporate safety features and creature comforts plus they featured updated, less utilitarian styling. As a result, more casual people were buying them and aftermarket support shot through the roof with vendors scrambling over each other to push product. If you took a Quadratec catalog for every Jeep model and eliminated the universal-fit stuff, the TJ catalog would still be the thickest. I suspect the JK is catching up quickly, though.
I enjoyed my YJ for its removable top and doors in the summer, but after owning my XJ for a while now I realize how impractical a SWB Jeep was for my lifestyle. I will probably own one again as a dedicated toy, but not as a primary vehicle.