And you are probably not the only one who hasn't replaced his anode rod for one reason or another.
I guess that home builders just don't care or realize that an anode rod needs to be changed every so often or perhaps the water heater manufacturers want them to be hard to remove so they can sell more water heaters.
I lived in Lubbock, Texas for 10 years and twice when I returned home, I saw water running out of my garage. The water heaters were in a closet in the garage. Lubbock has very hard water and the water heater bottoms would rust out spilling all the water.
I did not know that anode rods were made in segments - should make removal/installion a little easier if you can remove them at all.