California burrito is a SoCal thing, centered in San Diego. It's practically unheard of in NorCal. There's a few places that do it in San Francisco but it's not standard. Like any regional specialty, finding it outside of the region is often a challenge.
If you find a place that serves both french fries and burritos, you can usually talk them into making it as a special order. The problem is, outside of SoCal, there's not many places that do both. Another dubiously stoner yet pretty amazing combo is subbing broken nacho chips for the rice.
