Is this a bug or are you allowed to take Stuff from NPCs if their disposition is high?

When I first came to Whiterun all the stuff in the shops had the red Stealing tag if you looked at it.
Now after helping them most of the shops will simply let me take everything that is worth about 20g or less.
However some Bosmer I (seemingly) can't stand wont.

Bug or feature?

Featured bug?

Working as intended afaik