Why do we buy cribs?

Yet another crib problem people forgot to mention... now that my 8 1/2 month old has 4 teeth he has starting chewing the railing on his crib. He has completely destroyed the finish on his very expensive crib. I am off to buy a teething guard for the railing today which costs less than $10. Why didn't someone try and sell me one when I bought the crib?????????