Helmets off to those who lead these cross-country trips. I've led club rides and a few multi-day rides with friends... but also have a sense leading/staffing an extended trip like this with paying customers is also a bit different.
I've also done a few extended rides as a customer (e.g. three TDA rides, two Spice Roads, a BikeChina,...) and the group dynamics were surprisingly varied between them - so I also get a sense of a bit of "luck of the draw" involved even with some common client types.
I wouldn't expressly go work for a company staffing trips with strangers. However, also wouldn't shy away from organizing for friends.