The other day I was walking with my cup to the Soda Fountain1 at a restaurant. Someone was already using the fountain, but the drink they were getting was on the far right side, while what I wanted was closer to the left.
Figuring I had enough space to comfortably fill-up at the same time as them, I walked up and started to fill my cup...and proceeded to get a stink eye from the other person using the fountain.
This didn't result in more than a glare, but it did make me uncomfortable.
How can I tell when it's appropriate to use the Soda Fountain when someone is already on it in the future (as opposed for waiting for them to be finished)? Is there some etiquette on how far away the two drinks should be for two people to use it at once?
How can I tell whether or not I should wait for someone to finish, or step up to use the Soda Fountain at the same time as them?
1. For any unfamiliar with a "Soda Fountain," find a reference image below