As snobby as people from hillsborough or atherton or los altos hills.
Your description between RSF and CV is probably more due to age and wealth. RSF folks have made it, probably are older, and less to prove. CV folks are younger, up and coming (as you describe), and probably have more to prove. The worst are the soccer moms in those Land Rovers that don’t work. Blah blah blah blah blah blah blah…(We avoid them like the plague, so most of our families are double income folks that are pretty normal.)
However, you’re going to find the “rich kid” issue in RSF and CV probably equally, it will just come in different flavors.
I think the first thing to note is in general, SoCal tends to be more shallow than NorCal…Just look at how many cosmetic surgery places there are here and plenty of big boob people as far as Temecula (so I’ve been told). It’s just different down here.