text: I agree.  I have never understood why people are allowed to deduct interest on 2nd homes either. People can buy an RV or popup trailer and call it a "2nd home" and deduct interest on the loan.  No, I'm not making that up.  I'm guessing the 2nd home deduction is because many Congress members, at one time at least, had 2 homes, one in their district, one in DC.  But that's another topic for another day.
  
  We just can't afford to subsidize high mortgages and high local taxes.  We don't subsidize the entire cost of sending kids to college - that tax credit is $2500.  We don't subsidize the entire cost of raising kids.  We don't subsidize all of people's healthcare costs (frankly, the amount we allow for that deduction is too low, imo). We limit how much people can shelter for retirement.  There are many areas that the tax code allows some deduction in order to encourage a particular activity, but not unlimited amounts for people to spend on that activity because they can afford it.