[lenaitch]

One snag I have heard of is teachers, TAs, etc. who work in multiple schools for parts of the day. If you are a full-one school employee it is relatively easy - charge per day. If you're in-and-out at several locations, it becomes something to be managed.
No doubt employer-provided parking will show up on the CRA radar at some point as a taxable benefit. They're already looking at employer-provided phones.