Couple of points
A good manager is training someone to replace them, else they can't be promoted. Thats part of being a good manager. It might not be out in the open.
I'm lucky. I have a decent senior management team that trusts me. So other than a few raised eyebrows on overtime(not mine, my staffs), and a few reviews of travel costs, I don't get a hard time about spending money on things I need to do my job.
James