Cold water should always be on the right side of the faucet and hot on the left. This is an industry standard throughout North America and applies to single lever as well as dual faucets.
When indoor plumbing was first introduced, there was one option that came out of the hand pump: cold water. Since the majority of people are right-handed, the pump was placed on the right side of the sink.
The logic for keeping the cold/right, hot/left placement – is to avoid surprises. We tend to reach for the right side first and by having the cold there, it helps to avoid accidental scalding.
We won’t “tell” on this local Austin business, but we do urge them to give us a call!