Customers requesting a "glass of water" - some will ask the more apt "cup of water" - on the side is growing in popularity. Maybe they are feeling a little dehydrated or want to clean the palette before their drink, keeps you on your toes just in case they are cofficionados.

A surprising amount of people end up leaving it on a table or the condiment bar without even attempting to drink it. This must be a praise of our quick service feeling it unnecessary to need the water when their iced drink arrives.

Or perhaps they are hoping for free merch glass cups...