Earlier this month, I finally got some use out of the CHAdeMO adapter that we've owned for the past two years or so. It was quite handy to be able to fast charge in a town (Palmdale, CA) that lacks Tesla Superchargers. We were staying overnight and lacked the ability to charge at our accommodations. We needed a 90% charge on our Model S 85 before leaving town, as we were planning to caravan with a group the next day and wouldn't have time to stop at a Supercharger.
While this might have been a bit of a corner case, the point is that you never know when it might come in handy to be able to charge at a non-Tesla location.
On a somewhat related note, I'm in favor of using a Tesla Wall Connector at home so that the UMC (Universal Mobile Connector) can always stay in the car. We've had Tesla owners come to our house to charge (we're in PlugShare) because they forgot their UMC at home and found themselves unable to charge at their rented cabin up here in the mountains.