Right, if you think all they are capable of is lean-to's and teepees you have missed their messages that are sometimes difficult to see (sometimes next to impossible). It will test your tracking and observational skills to the nth degree. If you are uber familiar with a section of real estate it can make it much easier. The manipulations that occur between dusk and dawn-- if you are close enough to investigate-- can be very eye opening.
Sure I have engaged in fort building before the woodscraft and survival shelters were but a figment, grew up in the age of the early USAF survival manuals from the 50's. My adventures included ground excavations and tree forts mostly.