I mean, the definition on Google is:

peasant (n.): a poor farmer of low social status who owns or rents a small piece of land for cultivation (chiefly in historical use or with reference to subsistence farming in poorer countries).

I'd assume they just aren't familiar with how you're using it

That's a personal problem. The demographics and political power of Marin county residents are public knowledge. I live/work in Marin county and the vast majority of residents are extremely wealthy. There are exceptions, but, as one of those exceptions, I can understand why they are blocking the golden gate bridge and won't get pissy at a group of people who have made national news with their courageous protest against genocide.