Amazon.com sells 6 pack for 92.50 with free shipping and no taxes. This may be the best deal out there:
Babies R Us as usual the most expensive but sometimes they do have coupouns:
Target has decent pricing per can:
Walmart is the same price as Amazon but I would have to pay the sales tax (6 pack):
So around $60 dollars per month and going up. Soon it would be 5 cans per month. I found a Simply Right at Sam's club with the same ingredients for $23.28 for 48 OZ can! I wish I could buy that but the wife said no, only the best for the little one.
So yes... babies can be very expensive but worth every penny! The good news is we have saved closed to $1000 in gift cards just for baby stuff. I look at it as another emergency fund just for baby needs, hopefully we don't have to use it.