On 11/12/2014 4:22 AM, trader_4 wrote:

I would be surprised if Costco didn't know to
the penny how much their cost is to install a tire, including the nitrogen
and they keep that in mind when setting the price.

You keep making the error of believing that price are set based solely
on the retailers costs, when so much more goes into pricing strategy.

Look at gas stations. Right now you can buy a gallon of top tier
gasoline in my area for $2.80 or $3.60. There is essentially no
difference in the quality of the gasoline. The retailers are buying fuel
from the same refinery and the wholesale cost is almost the same.

Why does a station charge 80¢ per gallon more, knowing that they will
sell far less volume? There are valid reasons for this that have nothing
to do with their costs.