Shedding their old boring image, station wagons have become another segment that car fans pine for. From a practical standpoint it's easy to see why, as wagons can marry the cargo space of an SUV with the road manners and handling of a sports sedan. Like everything fun, this segment has basically gone extinct in America, replaced by innumerable crossover vehicles at every turn. This makes older wagons desirable on the secondhand market, which in turn attracts collectors, investors and speculators. A few decades prior, however, the station wagon was considered common and unremarkable.
After the Baby Boom, Americans naturally saw themselves with expanding families, and automakers met the occasion by crafting wagon versions of many of the cars in their lineup. Perfect for carrying three or four kids, plus all their required luggage. These models were based on hum-drum American sedans, so the results weren't particularly exciting. That is until the mid-60's, when the manufacturers capitalized so hard on the muscle car craze that they even started offering some wagons with 300-horsepower big block V8s. The modern image of the performance wagon would come later, out of Europe, with contributions from Mercedes and Volvo.
Back in the states, popularity of wagons started to wane when Lee Iacocca helped launched the minivan craze of the 80's, and really took a downturn when SUVs started eating up the market in the 90's. Station wagons were viewed as boring and obsolete compared to trendy minivans. The vans in turn were old news in front of modern crossovers. Wagons have a had a nostalgic resurgence among enthusiasts, lately. Particularly among Gen X-ers who have fond memories of road trips in the back of a Fairmont or Roadmaster. A few modern products have swooped in to fill that niche, such as the Cadillac CTS-V, Buick Regal TourX, and Audi RS6 Avant. In the case of the Caddie and Audi, those cars feature the powerful engines and high-tech suspension of their sedan counterparts, making them perform just as well as much smaller cars.
As we've seen with manual transmissions and naturally aspirated engines: the people who clamor for these things are a small portion of the population, but are insanely dedicated. Wagon fans will continue to keep the segment alive any way they can, and more power to them, as variety is the spice of both life and car shows.