Taco Bell is considered fast food. I've never heard of Taco Cabana so I don't know what that is. :)
Is Taco Cabana and Taco Bell considered fast food?
Taco Bell is fast food because they have a drive thru and everything. I've never heard of nor eaten at Taco Cabana so I can't answer that for you.
I know Taco Bell is as the food there is about as Mexican as I am, which is none. I'm not real familiar with Taco Cabana but from what I read about it, it sounds somewhat better than Taco Bell. We have El Pollo Loco here which is probably comparable to Taco Cabana. They make really good authentic Mexican food !
Taco Cabana sells more of the type of food that requires a table to sit at in order to eat comfortably.
You might consider it has one "foot" in fast food and the other in restaurant style food. (Sorry for the awkward image of "foot.")
I used to eat there on a regular basis for a while and then started going primarily to sit-down Mexican Restaurants with waiters.
Its all good junk food with shine.