If the people you know bought Jeeps in decent condition and did the required service on them as need, they would have no problems. My first Jeep was a 1993 Jeep Grand Cherokee my parents bought brand new off the lot. It now has over 220K miles on it, and nothing major has happened to it.
Other do doing typical service, replacing batteries and tires on it only the fuel pump, alternator and CPS have gone out. All of that was after 200K. Not many ricers will make it to 200k, and if they do, they are running on three of their four cylinders and sound like glorified sowing machines.
And in all honestly, 20MPG isnt that bad. Ya so it doesnt get 32MPG, but if you want some thing better than that, get a decent car that will get that, say like a VW Jetta TDI that gets 45+MPG. Having an SUV wont break the bank at the pump. An extra $10 to full up isnt going to breakup you either.
And as for the people thinking just b/c they have an SUV they think they are invincible? Thats like me saying any one who drives a ricer must be a little highschool shit and thinks just b/c he has a NOS sticker in his back window his car is fast. I know how to drive in snow, I know how to handle my Jeep, and Id prefer having four wheels push me though the snow than two.
You seem to know nothing of Jeeps, or demotic cars in general. And it sounds as though you dont know jack about four wheel drive vehicles either. So tell your parents you want a little ricer Toyota when you graduate. When you get a rear car, or become ASE certified come back and talk to me about cars. Until them shut the hell up.