Being able to jettison military items from stations and selling to Black Market stations without consequence is pretty broken in terms of moneymaking
Especially since you can resell the same item repeatedly (example: dual Tev9 at a Black Market Station in Belenus / 1 system after Sirius)
For example, the station guards could turn hostile, etc. etc.
The power has limits. Each time it is used more than once against a given sovereign, there is a chance of failure. After too many uses against any given sovereign, it always fails, and there is no way to reset. Jettison is a power to be saved until you find that big ticket and/or ultra-rare item you really want for free, use it for your first (or second) time, and you get it the item guaranteed. Waste your Jettison uses on frivolous stuff early, and you will not be able to use it successfully later on important items you really want.
True, Jettison is very strong, probably overpowered, not unlike pilgrims getting Ingenuity for free permanent item buffs (that greatly inflate resell value) or Desperate Escape making the playership impossible to kill in combat (long enough for player to use an item to escape). Jettison is almost worth giving up the overpowered powers the pilgrim gets.
The point is Jettison probably has enough limitations that additional risks may not be necessary.
The amount of uses you get is honestly more than enough, especially if you get the AI up to level 6. And particularly as there are sufficient friendly factions in EP.
Especially so since it also affects the entire stack of items, which meant that I could grab several Level 8+ weapons / etc. in one go.
Using it on "frivolous stuff" early allows you to powerspike up faster, so you can powerspike even faster by rushing a late game system, so I really don't get your point - like, what would you say want that you wouldn't be able to earn easily after getting a huge powerspike? Say perhaps Eurasian Diarchy weapons that require a letter of marque*, well, then don't use Jettison on their stations until you see what you want.
*Not the lower tier ones that can be acquired from the late-system station guards
You don't need to do it many times to say, buy your way up to a Minotaur after doing a mad-rush to one system or so beyond Jiang's frankly, which is enabled by using it "frivolously" in the early-ish game.
N.B. My most recent experience, YMMV
That being said, I did beeline levelling up the CDM quite a bit