> The weirdest part to me, receive a call and just get up and go? Priorities?

The author does contracting in niche topics. When your contracting domain is uncommon you have to go where the work is.

You can charge higher prices for niche work and therefore tolerate more time in between contracts. This person may be spending more time not working and with his family than the typical FTE in this arrangement, even if the jobs occasionally require them to fly somewhere for a month.