My time in the public service was quite different to yours...while my department didn't do much o/s travel, there was a lot of domestic travel. If you needed to be in Canberra on Thursday, you would leave on Wednesday. It was all about making sure that people rocked up ready to work, but also weren't wasting work time being unproductive or travelling. Unless that was the best option (eg 4 people in a prius from Newcastle to Canberra vs each of those people in a taxi to the airport, flying, taxi to the cbd and back again...). We also had a very proactive ride sharing system for car trips to reduce the number of single occupant journeys. Have you ever considered that perhaps your boss just thinks you're a fuckwit and wants to mess with you? Most of your work related whines give me that impression...
Also most people I worked with hated travel. They all had lives...family, pets, sport, dildos, wine...fuck I don't know what normals do outside of work. They were all confusing to me! But they all had reasons to hate on travelling. Not me! I loved the opportunity to bludge! And get the travel perks...always came home with cash in my pocket and a smile on my face.
Lastly I'm pretty sure the "travel for work" fbt and deductibles stuff has been tightened up a fair bit. Shit like splurging on conferences has really been reigned in, making it difficult to do a 2 day conference in Hawaii on breast enlargements and a 5 day golf retreat all in the one journey.