I'm in Canada, where tipping is just as expected as it is in the US. However, here it seems that 15% is standard for good service; 10% for fair service or a buffet/brunch meal (where the server was less-involved); and 20% or more for fantastic service. I had no idea California was so high.
Servers in all proper US/Canadian restaurants have to "tip out", which means paying a percentage of what should have been their tip on any table to support staff (e.g., bartender, host, kitchen). A server can tip out as much as 5% of the pre-tax bill --- or 1/3 of the expected standard tip --- which means that if you leave them no tip, they actually have to pay to serve you.
Interesting; in the US it's common practice for all tips received to be pooled, and then divided among the waitstaff, busboys, etc. I'm not sure if they're divided equally, but everyone should at least get a pre-decided portion.
Servers in all proper US/Canadian restaurants have to "tip out", which means paying a percentage of what should have been their tip on any table to support staff (e.g., bartender, host, kitchen). A server can tip out as much as 5% of the pre-tax bill --- or 1/3 of the expected standard tip --- which means that if you leave them no tip, they actually have to pay to serve you.