My work uses it to have a standard approach to our website. The website I’m working on (with my team) is approximately 8000-9000 pages big, and we use templates based off of Foundation to do our work (after I bug tested them.)
Why? We’ve had people leave mid project so far. We’d like our code to be standardized. We don’t want to worry about cross-browser testing every page (test the template, then everything should be good!)
I don’t use frameworks for personal websites since it’s overkill, so I see your point there.