Yes, agreed there's something hokey here. I've been mulling it over since I saw this post but in case I don't get chance to do a full response I will just say now that I agree this stuff needs work. And while I find the idea of being spotted by guards and being able to lie, bribe or go to jail really fun and I'm glad Larian are trying to include it, that element is particularly wonky in practice!
With respect to NPCs noticing stealing behind them, I think I did see a post from another forum member saying they'd had confirmation that the mechanics had been changed here, and that NPCs will now hear, eg, chests opening and closing and turn to look. Which sort of makes sense if the rogue is interacting with something necessarily noisy, but otherwise I'd agree that they should roll a perception check against the rogue's stealth to see whether the rogue manages to silently open and close the container.
