1 – The coffee tastes like shit so I’m never tempted to order one
If I forget myself and accidentally order one I certainly never order a second (I usually drink hot chocolate in Starbucks).
2 – You have to pay for wi-fi so I’m never distracted by IM/IRC/RSS
In the UK, all the wi-fi at Starbucks is through T-mobile who charge £30 ($60!) a month to use their hotspots. With a 1Gb download limit.
3 – The ‘comfy’ chairs are really uncomfortable after an hour or so
One of the biggest issues I had back when I was working in a coffee shop all day was that I’d get too comfortable in the chair and not move around as much as I should (eventually I got tendonitis). At least this way I always get up and leave after an hour.