I guess this is going to depend heavily on the kind of job you have.
My workplace provides coffee of the highest quality, breakfast, snacks and all kinds of drinks. I also get access to ~$10 per day to spend on lunch - which to be fair doesn’t really cover the whole cost any more - but still, it helps. I also bike to work, so there’s not really any cost there to speak of.
Depending on how creatively you decide to do your accounting, I arguably gain from going to the office. Then again, I could spend 5 days at home if I wanted without any problems. I’m choosing to go in anyways though
[What If?] Would a Submarine Work as a Spaceship? ( www.youtube.com )
'Wildly more expensive': Workers with in-office jobs spend about $31/day that they wouldn't working from home — here's what employers need to do ( finance.yahoo.com )