The Tesla adapter from Tesla is J1772 Female to Tesla Male - it's made for Teslas to use non-Tesla Level 2 charging. It won't allow you to use a Tesla "destination charger" to charge a non-Tesla or to use a Tesla Level 2 home charge station to charge a non-Tesla.
If you have some other kind of non-Tesla adapter that's Tesla Female to J1772 Male I'd be wary of it.
The "free" Tesla charging you're thinking of is Level 3, DC Supercharging. It's a moot point, though, because the Clarity PHEV can't accept DC current - and the Clarity EV has a CCS charging receptacle for Level 3.[/QUOTE
I think you are mistaken about the tesla chargers there is one where I work. Just level two. I saw the paperwork from Tesla the owner of the building pays for the electricity and the install. For that Tesla will give the charging equipment to the building owner for free. Also states it will show up on the tesla network of chargers. Anyone can use it, there is no way to collect money for its use.