Let's be real, the reason this is happening on Metastation in particular is because of the extra gamer gear in the vault on that map. Besides the piggy bank, an insignificant amount of gold/silver, the useless belt and the secret docs that have zero value to anyone but antagonists, the metastation vault has these items in the safe.
https://i.imgur.com/tLQnNQG.png
Duffel bag just has a full set of clothes including gloves, the silver id is a real silver id but it starts with no access. The disabler is the clear goal here, and I posit that the accused is breaking in for this disabler because they are a weenie baby who is too scared to mug a security officer for one or feels that they wouldn't be able to justify this gimmick if they were breaking into security's areas and smashing the lockers. Maybe they can't muster the courage to attack brig's lockers and aren't satisfied with the items from the departmental/aux security outposes because those lockers got nerfed because weenie babies kept breaking them for effort-free loot. Maybe they just feel that cargo is easier to beat in a fight than security.
If the admin steps in to say "keep this shit to antag rounds please" then fair enough, surely? Experimenting with breaking and entering and practicing committing minor crimes is fine as non-antag, but how much of this is honest experimentation with the game for gimmicky reasons and how much of this is just gamering a disabler and spare anonymous identity every round for an advantage? It's not even as though antag rounds are terribly rare right now, especially conversion ones like revs.
Furthermore: if those items are crucial, there are other ways to get them. The most obvious is bribing the damn QM for the items. You could do a single bounty and that is usually enough for cargo to buy you a disabler crate no questions asked, they might even break it open for you. Same with the silver ID. You could play any of the cargo roles and just buy it yourself.