Tap Water Please??

Note– Spain's water is fine to drink! Especially if it's filtered. My host parents' house has a filter, so I can drink the tap water thank goodness. Most restaurants have filters as well; however, they will pretend that their water is the dirtiest thing on earth to get you to buy bottled water. Every time I go to a restaurant and ask for "agua de grifa," the waiter looks at me with annoyance, and after discussing that yes, the tap water is fine, reluctantly brings me a free glass of water. So different from the U.S. where tap water is expected!