Almost every time we are charging away from home, we are at some event. It would be a pain (or in some cases not really feasible) to go move the car when it finished charging, but the concert has another 90 minutes to run.
If the chargers are oversubscribed at your office, its an indication that you need more of them. Add them, and do it in the back corner of the lot, to get past the "deluxe parking" idea. Giving free charges, and outright subsidy to EV's is one of the cheaper ways for a region to improve its air quality scores. Yea its a tiny effect at current market share, but solo HOV in California, sold a lot of priuses while the program ran, and it is selling a bunch of leaf's now. Some people will get a second car because it would shave a half hour a day sitting in traffic...
Luckily New England seems to be Chargepoint territory. Since Mass makes it difficult to legally resell electricity, (laws to keep landlords from sub metering, and adding a hefty markup) most are either N/C (usually business "sponsored", or just part of the regular exhorbatant downtown parking fee at a garage) or at worst charge a flat rate per hour while charging. (the only explicitly pay one that I regularly use is flat $0.50/hr for up to 6kwh fed. Stop charging, and the meter stops. Cheap for us, not so much for volt, or other 3kw machines. Yes it does mean it isn't available sometimes. More annoying about it, its a two head charger, with the second space dedicated to a Zipcar plug in Accord. Which the renters never plug in when they are done with it.... )