The mob mentality leads to situations where we round up everyone who is Japanese, Jewish, Homophobic, etc. and get rid of them.
One of these things is not like the other.
Also, there doesn't seem to be any evidence of people "rounding up" donors to Prop 8. Eich was appointed to lead an organization whose values he didn't share, and represent them to the public. He was unapologetic about this. This isn't a situation your parents or pretty much anyone else would realistically find themselves in.