I like ice water at a restaurant. It's a very American thing, I know, but something I've grown to appreciate after ~5 trips to Europe (business/pleasure). Another mildly interesting thing I've noticed is that Indians (not American) abhor ice in their beverages, nearly universally. We go out for a business lunch or dinner and they nearly universally ask for their drinks with no ice. In asking a few they've told me that they want to maximize the amount of "drink" they get, whereas the ice takes up too much space making it a worse deal I guess. Refills in India aren't a thing except for hot chai tea.
I've been told Indians prefer lukewarm water because its better for your body as it goes down. Don't quote me on that.