The Chevy dealers that I have
The Chevy dealers that I have encountered (including the one where I purchased my 2017 Bolt EV) have a (2) L2 chargers (usable by anyone & any brand just like the Nissan dealers) and DC Fast Chargers (one inside and one outside). You usually have to get permission to use the DCFC. I'm on the East Coast in the Philadelphia, PA area. Now this is as of 2018. In 2017, while most had L2 chargers in 2017 the DCFC were absent.
So it appears things are changing. BTW I love my Bolt as every Bolt owner I have encountered; It's not just a great EV , it's just a great and versatile car.