I asked the question on Twitter, but I don't know if I'm going to get any real answers or any answers at all over there. Here it is:
What's the appeal to taxing inheritance differently than other types of income? Aren't flat taxes bad and regressive?
I've occasionally encountered emphatic support for a 100% inheritance tax, but I'm never sure if that's not really a joke coming out of people's frustrations with nepotism and generational wealth accumulation. It seems like there are better ways to address those things than making exceptions to the progressive income tax.