I've worked at places specifically didn't want to send employees to conferences because they think everyone uses them as farming tools (whether that's true or not, some engineers just want to go learn and it's pretty upsetting if you have a SME in some subject and don't allow them to attend a con while plenty of other $leaders go).
I've also worked for tech places where a boss would come in and fire you on Monday then call you up and offer you $1k to return on Tuesday, me being about 21 at my first sysadmin job kept me around for that abuse.
It's really, really not a good feeling to feel untrusted or like you're constantly being tested by your employer.