I agree it is just that I have read on some Forums where people think they should get the same battery that was in the vehicle...with the same warranty thus getting another 3 or more years...I don't see how any manufacturer could do that and remain in business...
I will add that the battery replacement was done by the previous owner on his Interstate battery and that the Ford F150 it went in to has two battery options and perhaps the installer either didn't have the same Interstate to replace in that level or just checked the lower replacement options...
In any case, when I got it and after a particularly rough Winter, I replaced the battery with a Walmart Everstart Maxx that was made by the same company as the Interstate (Johnson Controls) and was about $15 less than the same Interstate on sale at Costco...
Bill