I try. Sometimes we run out. There's usually a bottle of red around.
I'm having a hard time imagining not having anything available to offer guests. I know not everyone wants (or can afford to buy) wine. (I do seek out inexpensive wines, which can be had even here in PA where everything comes from a state store.) But coffee and tea are cheap and so easy to keep around. I'm pretty sure my mom kept stuff around for guests. I'm QUITE sure my Georgia born-and-bred MIL has always done so. :-)
We don't keep caffeine in the house, or drink it. Decaf is caffeinated, so that's a no too. We don't drink milk, either, so really all we ever have to drink is water, because that's what we drink. I promise we are not bad people
We do have some medicinal teas, but I don't know if anyone wants Throat Coat when they're not sick.
I buy cookies but we eat them when I buy them. Same with most snack foods - that is how I keep the kids (and me) from constantly eating only snack foods. We have fruit, often, and celery and peanut butter, and etc.