As a person who supports of individual choice where reasonable, I encounter this argument regularly. That is, if I have a different opinion regarding the balance between personal liberty versus collective responsibility, then I’m morally inferior. I generally find such arguments exercises in self-promotion (e.g., I’ll pay more because I care about other people).
If I’m given a choice between individual liberty and government control, I choose liberty. That said, it’s a false argument to say that personal liberty requires freedom from taxes. It’s an equally false argument to say that the more you care about humanity, the more taxes you should be willing to pay.
I used to live in Massachusetts just as you do now. I watched the state government waste enormous amounts of money (e.g., the Big Dig) and indulge in numerous cases of personal corruption while demanding increasing amounts of tax. You’ll therefore need to pardon my lack of wide-eyed belief in the inherent goodness and efficiency of government spending.
If you’d like to argue for higher levels of taxation and increased government control over the spending of its taxpayers, you are welcome to make those arguments. We can discuss whether governments or private industry provide better results. However, I think it’s cynical and self-aggrandising to insist that only one side of an argument cares about humanity.