Take some investment property. You buy it at some basis price, let's say 500k. You rent it out for 15k a year. Each year you can offset your rental income against deprecation of the property and property taxes - meaning, you pay no income tax on your rental income.
~30 years later, you've deprecated it down to an effective value of $0, so you hypothetically would have to start paying taxes on your rental income(of course, you can still deduct property taxes against that). What do you do? Well, there's something called a 1031 exchange - this lets you sell an investment property, and as long as the funds go directly into another investment property, you pay no capital gains taxes. So guess what? You can buy a brand new investment property with a new(albeit adjusted) cost basis, and you can start the entire cycle of depreciation and deduction all over again on your new, more expensive, property.
So, you've now held this property your entire life, and you die and pass it to your kids - well, great news, unless your estate is over 12 million dollars(and double that for a married couple), you pay no estate taxes. And even more fun - when you inherit property, the cost basis is "reset" to the present day value of the property at time of inheritance - So your children can now rent the property out, deprecate it, and pay no income tax on the rental income either, and continue the cycle.
The net result is that rental properties generate a ton of income for the owners, who pay almost nothing in taxes. Even if they do pay property tax, property tax rates are generally much lower than income tax rates.