Just throwing this out there to see if it sound like a good idea.
What about the San Diego Brewing Company parking lot off Friars road?
10450 Friars Rd, San Diego, CA 92120
Several restaurants, huge parking lot, auto parts across the street. Possibly crowded. Traffic if coming 15 south before ~6:00 PM. Don't know if this is closer or further for most.
P.S. - Found the awning mounting screws when I unfurled it last night. Thanks for the suggestion on the exhaust clamp mount for the roof rack side. Did some measuring and it should work perfectly.