I agree it needs to change.
In the real world example of a lorry ( I dont really know what that is...) could you take things from it? No. But in real life, deep ocean salvage teams lift up cargo all the time. International waters and whatnot... seems like independent systems fit the ticket just fine for that.
Items should be "stolen" when they are forcefully removed from other players / NPC's.
Items should be "salvaged" when they are sitting in space, unclaimed.
This is exactly how I think it should be.
Other things that could be implemented:
1. Buy a salvage license. For xxxx amount of credits you have a license to salvage things floating in space.
2. With said salvage license, the floating debris has to be out in space...unclaimed for xxxx amount of minutes. This gives the "owner" time to return to reclaim their property. If the timer is expired...it's up for grabs.
3. Said salvage license needs to be renewed after xxxx amount of cargo tonnage is returned. (This part may or may not be left out.)
Another route for this is a "Lost and found" department. You can return it to a space station for a "Lost & found" reward which could include a rep bonus.
Using the example of finding something on the side of the road and taking it can be applied to, if I find a hat on the ground in a grocery store & I return it to its owners or to a lost & found department doesn't mean I'm stealing it, does it?
Picking up stray debris in space & being marked as a thief needs fixed. Hopefully the developers will take this to another level. This part is too cut & dry.