Do you get angry when someone mentions London that they didn't specify that it is London, England?

Because there are other Londons.

Thank you for your interest in my emotional states, and you make a good point. However, I don't think these situations are the same.

In terms of population, the biggest London is 9.1 million people and the 2nd-biggest is under 500,000. Quite a big difference! I think that's why when someone says "London" one can usually reasonably assume they're talking about the one in England, unless otherwise specified (or unless they live near a different one).

The biggest Orange County is 3.1 million and the 2nd-biggest Orange County is 1.4 million, so the difference is not nearly as great. I'd even suggest they're in the same general category of size. In the context of a national/international website, it's far less clear that one of the "Orange County"s is so overwhelmingly what people refer to that its state need not be specified.