For me, I only have to read the 'checked in on the wrong day / left my car at another airport / forgot where in the world I was and had to ask the FA etc' threads. Those sorts of things create a face-palm moment, but if they are being done, can you imagine the silly mistakes that are being made in business-critical situations? Whether you are fixing critical machines, or negotating a major deal, you need to be at the top of your game, as mistakes can cost both money, and for some industries (say, aviation) lives. Sure, if you are bobbing over to attend internal meetings, give academic lectures etc. it doesn't have the same consequences.

You poo-pooed the suggestion that being tired and driving on an autobahn was an issue. Driving tired can be as dangerous as drunk driving - add in the 150mph speeds on an autobahn, where reactions need to be even faster than normal, not lower, and it is a recipe for diaster. It's nothing to do with sucking it up and pulling through a difficult situation - it's basic common sense and safety. Now, there are other ways of doing it (for example, flying in Y the day before, spending the night at the airport hotel and driving down the following day - been there, done that), but I sure as heck am not going to spend a day of my own time (weekend day or personal day) doing so, because my company don't value me enough to pay J. If they want to send me down a weekday early, ok, I can live with that, but as others have said, the cost of my time for the extra day, plus hotel, plus meals etc. isn't all that different to a discounted J ticket. Not to mention, losing 1/5th of the work week this way soon adds up to a large amount of lost productivity.

For me, it is simple, I shouldn't benefit or suffer as a result of my work. I sure as heck don't pay for F when I fly, so nor do I expect my company to do so. But likewise, I also don't fly a long distance in Y and then pick up a hire car, so nor should my boss expect me to. Fortunately, all the firms with whom I have travelled have been reasonable - J over X hours, or J for outside of N.America etc. I personally wouldn't (and haven't) taken a job which insisted on large amounts of Y travel - for me, it is simply not worth the consequences to my health (previous injuries making bolt upright travel painful and I suffer consequences severe enough to need a trip to physio / chiropractor / massage therapy and some painkillers when I do).