Folks need to plan for the costs. It shouldn't come as a surprise to anyone that waterfront property is valued higher and comes with a higher tax bill. Same with your more expensive cars, or boats, or whatever.
Are property taxes high? Yes, they are (relative to other states). But the
overall tax burden in NH is still lower. And I'd rather be paying higher town property taxes over which I can exert some influence in the voting both or town meeting each year rather than translating it into sales or income taxes which, once implemented at the State level, are virtually impossible to influence.
I had to laugh at the fallout from the Massachusetts "Tax Holiday" a weekend or two ago, and the State's complaint about how much money they lost. They lost? Who's money is it?