In one of the years, the location was Boeing Field in Everett, WA where Matt said several of their journeys have started.

Using private jets comes in handy when plans have to change. This year, for example, NBC had to switch the locations of Day 2 and Day 4 due to bad weather in whatever location the original Day 2 would have been. So Matt and company had to get up to Madrid instead of wherever the unrevealed location would have been. Trying to cover the distance on commercial flights at the last minute could be impossible for some locations.

But commercial flights are used as well. There's rumors going around that Amy Robach flew Singapore Airlines to get to wherever tomorrow's location will be. And with some locations needing over 200+ boxes worth of equipment, ferrying all the supplies and crew by private jet for all the locations would get pretty expensive.