It’s all about range. Out west it can be a loooong way between stations.
I get that. Not as much as I used to but have ridden out west a lot. Long enough ago when it was far less developed than now. And even now you can find long stretches of nowhere. Even with the old five gallon tanks and even 40 mpg, and filling up at even early opportunities to make sure you did not (and not have) later ones, it was always manageable.
There are places you definitely want to think/plan ahead. GPS units with pre-mapped fuel locations certainly make that less worrying than it was a billion years ago as well. All told, however, I ride for the zen, for the feeling, for being there. Fuel use is monitored, sparingly, for completely other reason than dollars per ride or actual miles per gallon.