Why is the water fountain always next to the restroom???

Why?

Minimizes plumbing material/cost.

Good point. Maybe we need a water cooler section, where we maintain a “business casual” type of discussion. And we also have a “restroom”, where we talk about colon cleansing.

+1 This is the same reason bathrooms tend to be in the same place on every floor of an office building.

So the water we’re drinking is the same water filling up our toilets?

^Yes, it is. It is the exact same water.