So, after you finish a relatively straightforward quest, once the brotherhood of steel airship shows up, they invite you aboard and hand out a suit of power armor.

The shopkeeper on the airship has a master locked door protecting him. It is not red. So I picked the lock (they commented on how I was handy with that thing).

I then dismissed a certain Paladin who would look upon me stealing negatively from my party. Dropped into the crouch, and stole everything in the shop, right under the nose of the shopkeeper. Notably, there are several fusion cores, the GAUSS CANNON, and a helmet for the best power armor in the game (X-01).

Seemed like a no-brainer. This is way better stuff than you can possibly get at this level. Will there be negative consequences or can you steal from anyone if you want? It was also, frankly, too easy. I had 0 stealth related perks. The shopkeeper is too stupid to watch me - most shopkeepers in this game and skyrim will follow you around the shop and keep you in sight. And, it just kind of defied logic that I could literally steal everything but the shelves in the shop and nobody suspects me.

I'm confused about this as well, from what I understand there's no Karma, just pissed off people if you steal from them and they find out.