Why do people have such large trailers?

Lance72 wrote:
In fact I spent a week on the rd recently and didn't see more than 4 people per trailer.

Spend an entire summer on the road in that 19' trailer, instead of "a week," and you'll answer your own question. In 2013, we spent 3 months in a 22' TT and towed it for 10,000 RT-miles to Alaska. Earlier this year, we bought a 5th wheel trailer and a diesel pickup because of that trip and several other month-long, non-peak season trips. And it's just been the two of us on all those long trips!