Ok so...... silly question.

I know this pine based litter says it will last forever and it's great for the environment. Great btw!! I have done some "googleing" (so not a word!) on it and they all say they are 100% recycled pine. Great again!!!
My question is........... If this pine stuff is made with 100% pine than why pay the money for a small bag ($7.99 up) when you can go and buy 100% pine based softwood bedding (shavings) in a huge bag at hardware stores (78litres I think which expands 3 times the size) for $5.25? Is it the pellet shape?
I am using the shavings out in the catuary. The kitties have an area they use and I just cover it with the shavings and clean as necessary. Then I can use the shavings as compost or mulch. I also have it in one litter box until they are used to it and then it will be in all of them.