The farther you are in life in your job, personal life, friends, the easier it is to live enjoyably with spending less money through work trips to fabulous cities, automobile perqs, subsidized meals, work home-buying perqs, etc. I'm not sure how much these people are struggling with their low spending.
As a person who travels regularly for work I can say you have quite a romantic view of business travel. The reality is that I usually see (in this order) an airport, a taxi, a conference room, a hotel dining room and/or bar, a hotel room, a taxi, an airport. The idea that there is much downtime on a business trip is a fantasy of those who don't travel for work.
Indeed, I was surprised how little time we had for anything except of working and sleeping.