Well, the Core is the only lawful force in the Omicrons. They do just the same as Liberty Navy/Police, Kusari Nava Forces/Police, Bretonia Armed Forces/Police and Rheinland Militär/Polizei, just very, very extreme. Corsairs, as you are mainly playing one, are lore-wise not only a people of crimes, but also of cannibalism. Outcasts are doing the drug market, AI want to harvest all the ressources and SCRA wants to damage all the sirian forces - and Core sees all those guys helping the freeport. inRP, the action and reaction, aside from Jess' overreaction, are justified (more or less). There's nothing wrong with it.
I know, you and some of your friends visit Omicron Delta often for nomad farming, but you have to make yourself aware this system is of strong Core influence, because it's technically a Core system (bla bla bla but Order/Nomad/Zoners! bla bla bla - Core has just three systems: Rho is restricted and nearly nothing happens there, and the totally deplaced Capetown station in Omicron 94 is very hard to access, so it's also rare that something happens there, and that's why Core influence in Delta is very strong). And when you enter a system that is kept by a hostile-to-your-faction, you have to keep in mind a battle can happen anywhere for just the reason of you being there (Corsairs/AI/Outcasts/SCRA/Nomads (plus Zoners) and Core are at war). The same behaviors is mirrored when I enter the deeper Omicrons or corsair/outcast/SCRA/AI systems.
You and me enjoy PvE as well as most of the players do, but with more factions than just "good" and "evil", as soon as you enter this server, you can be attacked no matter whoever you are, whereever you are and also for very dumb reasons.