They have less gear/mods than 100% of "overlanders"

This is a pretty useless argument, but if it makes you feel bigger, go ahead. If your own argument can be used against you, probably just let it go. Do you need 10k worth of gear to go camping, instead of a ground tent? Do you need an SR5 Tacoma just to drive to work, instead of a 1994 Honda Civic? Do you really need the house you live in, instead of a 1 bed, 1 bath? Do you really need ice cream on your grocery list, instead of only essentials? Do you really even need the grocery store, when you can just garden and hunt? Do you really need cooking appliances when you can just cook over fire? Do you really need anything, when you can just be a caveman and cringe at everybody else? Its a never-ending argument. Enjoy your luxuries, and let others enjoy theirs. Just remember, while you're cringing and fighting for the internets validation, they're enjoying their lives (whether full of gear they do or don't use or not).

As for justifying gear within the US; yes, its justified. If they never used it once, and had it for "just in case," it was justified, because it was their desire, not yours.