well, for one, pickups are SOLID vehicles. you can buy one and know its not going to be pounded into a little pile by the roadway in 5 years, unlike a typical UJS. It can take abuse and holds up well to roads, offroad, weather and salt.
you can haul things in them. I was able to haul some pavers in my aztek last year. But mano, that rear suspension was maxxed out (no pun). Trucks (real trucks, no ridgelines), you can buy stuff at homestores and carry it home. Cars and fake trucks can't.
Resale. Pickups have even better true resale than even the most beloved UJS's. Buy a pickup, pay for it for 5 years and you can still find someone who will be pleased to pay you private party 60%, 65% or more what it's worth. Why, because it still has useful life left in it.
Comfort, for some folks, trucks are the only vehicles that provide real width or headroom or footroom. Easier to get in and out of. So many cars like the new Malibu are downsized so that only slight people can get in and out of them and have adequate space. Also, many love the secure ride and hadling and all weather capability of trucks. I know driving through blizzards, there is not much better than Suburbans, Tahoes, etc.
Safety. Who's gonna win in a crash?
Cost. Scan the paper. Right now, big discounts. The greater question is why people spend 40-50k on luxury sedans when for much less they can buy pickups, with cheaper insurance, maintenance, etc. Also note because of strong resale, trucks lease cheap. And you often might buy it at lease end because its worth so much. Lux car buyers just dump and move on to the next pretentious car.
Basically trucks sell because of what they can do and the tremendous value they bring. Mpg is really the only downfall of trucks aside from high center of gravity.
Also, trucks are great home business deductions, for self employed, aside from the more than you think amount of folks who have trucks for commerical reasons.
my dad says farm commodity prices being near double of last year, everyone is his area is out buying new trucks. One thing about farmers, if the year is good, they all go out and buy trucks, whether the one they already have is just fine or not.
Let me put it to you this way. My hometown is like 200 people. But they have a chevy dealer, and they sell as many or more pickups than the nearest GM megastore 30 miles away because they sell so many trucks. they never have new cars on the lot, but always a buttload of trucks, and boy do they sell.