They're saying that it's pretty silly to compare buying ice cream to being mugged. If it's too expensive, don't buy the ice cream. The price of ice cream isn't an invariant, if nobody buys it the price will decrease. If nobody has a problem paying $5/scoop for ice cream, that's what the price is going to be.

There's a convenience store chain where I live that has a "flavor of the week" available at $3.39 for a half gallon.

But if you want to lose weight, perhaps it's better not to know.