When you ask a waiter for water with your meal they will ask “gas or no gas”. This means carbonated or still water. They will not get a glass of tap water unless you specifically ask for it. Of course this is not always easy since not every waiter gets what you mean by “tap water”. In some cases they will also simply refuse to serve it I think because they don’t make if you drink free water.
I love the taste of plain water while I detest the flavor of “with gas”. I’m also cheap so I don’t want to pay for my water. I also abhor the waste of plastic bottles.
Historically, Europe has had issues with water quality and drinking tap water was just not a good idea. As a result people developed a taste for drinking mineral water and this culture has passed on from generation to generation. I was surprised while visiting some friends in Europe that they always served refrigerated. They thought it was very strange that we wanted just some water from their tap.
Some Europeans also believe tap water dilutes the digestive juices whereas wine and mineral water help. This is why you rarely see ice in drinks.