I think it depends on the situation. My interviews typically lasted all day. Lunch was included and I believe at least once I was actually offered coffee. Personally I wouldn't bring mine. I don't consider it a burden to go without for one interview. Plus I usually had some kind of notebook with me with examples of my work and a copy of the interview schedule that was provided to me as well as other documentation. It all becomes a bit too much to carry if you add coffee. But if it's a more casual atmosphere, no biggie. I mean, I wouldn't likely show up in a suit for a job at the Mc Donald's drive-thru.
On the other hand how does the coffee drinker act. Is this person placing a sweaty drink container on the interviewer's desk? Slurping loudly during an interview question?
So I think it's situation dependent.