I was working at a job that I hated. With a passion. Not the work, but the people. The project I'd been working on came to an end and we got shifted into another team with a manager who resented that she'd not been involved with the project and that her new team knew more about it than she did.
Anyway, four months later, an annual conference was being held in the Netherlands. It was free to attend, and I did every year through the project. I spoke to my manager and was told 'no, you're not going. We're not sending anyone'. I was pissed. This conference is hugely useful to my job role and was free. And these were the days of UK EU membership so going to the Netherlands cost basically next to nothing.
So, I book myself a week's leave and book my own flights and hotel, register, and go anyway.
When I get back, I'm called in to see her. Someone has grassed me up. I'm told it was hugely inappropriate to attend (it probably was) and I could have been seen as representing the University (i registered as independent) and could look to my employers that I was looking for another job.
I apologised and said it wouldn't happen again, but that they should consider sending someone in the future as there's a lot of important information there.
Just to piss them off, I booked a week leave during another major conference a month or so later and went radio silence on my social media. You could tell that they were really really suspicious when I came back to work (I'd actually had a week's holiday in Germany and Amsterdam).
Anyway, three months later I resigned and moved to a nice new better paid job I'd secured at the free conference