Just get a trader ID and be done with it. Real traders (as in those who use transports) get pirated and killed etc etc. It just happens.
The rule for neutral ID's was created by Igiss, as far as I know, and he wanted the neutral ID not to allow transports to force traders to RP and to make trading 'dangerous'.
House militaries and police ask you to drop your cargo, but should destroy it once dropped. The only place fines are used is in Rheinland, and that is perfect RP considering Rheinland's financial status in Sirius. They would try to get money anywhere they can.
And finally, do you realise how long the rules would be if we considered e v e r y s i n g l e loophole or stance on something? Excuse Igiss and the admins for thinking you might actually use your head...