I have no problem with Lindsey playing political fundraisers. I do find it tiresome when performers pontificate about politics to audiences at rock concerts, but a fundraiser? As FuzzyPlum said, they can do what they want "on their own time." Whether or not he shares my political opinion is irrelevant.
However, I do wonder if everyone here would be so "who cares what the performer's political opinions are" if Lindsey were playing a Trump fundraiser!