I will wager that 99 if not 100% of the time the spigot with the sign that says Non Potable do not drink, has exactly the same water you put in your fresh water tank. Why do they say not potable? Location and the fact that they cannot monitor the spigot for abuse.
Would I use the same hose? NO! Would I drink out of that faucet? No,but that is me other folks may feel differently.
When I was a small child my fathers uncle,an old time farmer had no plumbing in the house. He had a hand pump on the kitchen sink and it drained into a slop bucket underneath. The plate scrapings and kitchen refuse was also thrown into the bucket. After supper the bucket was taken out to the hogs and dumped into the trouth. Pigs ate it and we ate the pigs. My uncle lived to 103.