[dxdm]

Not all of them do. It's also nice to have one closer to you, so you don't have to walk to the bus stop to find out when it's time to leave house for the bus...

You could check on the phone, but I could certainly see the appeal of a fixed display in a convenient location.

[retired]

I don't really understand, don't you just go out of your house, go to a bus-stop and wait for the next one? Isn't the bus arrival display more of a convenience to know how long to wait? For the bus stop in my neighborhood I see busses every couple of minutes.

[tdeck]

You're very lucky to have high frequency transit. I've lived in several places (in cities) where the bus routes ran every 20-30 minutes. So if you don't feel like waiting at a bus stop for 20 minutes, often these days one without any seats, it's nice to be able to check the ETA.