Sorry for your loss OP! The game seems to have a LOT of quirky and weird mechanics.
Something Iv started categorizing and trying to raise awarness to in hopes that these things slowly get fixed.
https://forums.frontier.co.uk/showthread.php?t=86621 Maybe add the fine thing to the list of Issues I have raised here! I hope we can get Frontier to fix these annoying and frustratingly bad issues.
I agree with everyone else, While I have never once been shot up for a 300cr fine, Iv always been able to dock and pay it even when wanted, I agree that you SHOULDNT get shot up immediately if your bounty or fine is under a pre-determined number. Like 2k or something.
Theres a lot of issues with the current infractions/bounty/becoming wanted system in my honest opinion.
Ships can sometimes GIVE you a fine
A clean ship will fire at you and never get a bounty/fine, upon returning fire to save your ass, you get a fine.
Getting killed by system security after scanning a "Clean" target in Empire or Federation space with a kill warrant scanner.
The game posts "WANTED" anytime you get ANY infraction that isnt related to docking. Players see this and will shoot at you hoping you have some large bounty. They shoot first and ask later.
NPCs are NOT bound by the same laws that players obviously are. The only ones they seem to follow is the randomly generated ones for "Wanted" targets. I have sat there and watched a Type-9 Lakon bang against the inside of a space station for 35 minutes and never once get shot or blown up for loittering, on the other hand I have seen a smaller ship blown up for "loittering" while trying to enter the station.
Its one thing to have risks, its another thing to not have control of those risks and by just being you are risking the well-being of your ship and your in game life. IE what OP did and how he died.
Shooting a player for forgetting to get docking permission is silly and killing a player because they forgot to pay a fine less than 1k is even less intelligent and not defined under "Risks over Rewards
Sometimes fines have timers for no reason, I have yet to find out what happens if you do not pay on time. These timers do not reset if you log out.
Nothing tells you that you have a fine or you are wanted if you are NOT in that system. So while OP might of gotten it when leaving, he never once realized while out in the uncivilized part of the galaxy. He never needed too.. and further more, he shouldnt be forced to memorize something that happened 40 hours prior to leaving civilized space.
In summary: I agree, the fines are annoying. Theres TONS of issues with them and we need to make FD aware of them.