I think the uk idea of not opening a door outwards might be so you not forcing it without warning into an oncoming person. Such as some years ago I was running on the pavement and suddenly a car door was opened for me t run into. The car passenger never looked. Ouch ouch ouch. In my home, the front door opens onto my small front garden , little risk someone might be outside of it. However some homes have no front garden and such door would open onto the pavement therefore a risk of deflecting a passer by into the road and under the bus speeding past on the road?

