Isn't it more natural the выйти since it happens once?
That's the thing with Russian – you learn at school that a completed or one-time action requires совершенный вид (e.g. выйти) and an incomplete or repeated or continuous action requires несовершенный вид (e.g. выходить), and then you keep seeing occasions in Russian-language texts when this principle is (ostensibly) not observed. Like, why is it "Раздевайся!" instead of the logical "Разденься!" (take your clothes off), why is it "Проходите, пожалуйста," instead of the logical "Пройдите, пожалуйста," (inviting the guest to go from the porch of your home into the living room)?
One Russian woman gave me an example which made many things clearer to me. Maybe it'll be helpful to you, too.
Imagine that during a class, the teacher says to a misbehaving student: "Иванов, встань и выйди из класса!" ("Ivanov, stand up and leave the classroom!") Now, suppose the boy is taking his time getting up and the teacher gets impatient. Then she might say: "Ну давай, давай, вставай!" ("Come on, come on, get up!")
The first time, the teacher used совершенный вид, because the emphasis was on the result – to have the student out of the classroom. The second time, the teacher used несовершенный вид, because the emphasis was on the action – the student was supposed to stop wasting time and get a move on.
To come back to the OP's example, maybe when the Russians talk about getting off the bus at the next stop, they are semi-subconsciously aware that getting out of the bus will not necessarily instantaneous and smooth – there might be people in your way you'll have to make your way past and such. That's why the say "выходить" – "we'll have to undertake the endeavor of reaching the bus door and exiting".
Another thing to consider is that when Russians ask someone to do something, they often feel that несовершенный вид sounds more polite, more refined. They say "Присаживайтесь," ("have a seat") even though "Присядьте," would confirm better to the general rule in our schoolbooks.
Those are nuances we the students of Russian will just have to remember.