You CAN run in the common rooms

and inside houses. Only found out today, after a full playthrough slouching my way through the various interiors. Drove me mad. You too?

Just tap/hold the sprint button :)

edit* no I didn't WALK through the entire game. I just assumed when the game put me in walk mode in shops and common rooms and dorms that there was nothing I could do about it! I know i'm not alone with this so yay for everyone who knew it ALL ALONG I guess