It is cheaper to out-source them.
All types of footballs roll, as they have curved surfaces. Some footballs (soccer) are nearly spherical and will roll for greater distances. Rugby and Australian footballs are rounder and will roll farther than the tapered US footballs. Even the US and Canadian balls can roll for dozens of meters (yards) under the proper circumstances.
when did the US start using the metric system.
Yes...It Does Give Us Leather....
Well to start anteater and sea turtle. Also I believe human is frowned upon
All NFL footballs are manufactured in the Wilson Sporting Goods football factory in Ada, Ohio. It is the only football manufacturing facility in the US, and has been making NFL footballs in the same building since 1955. The entire process is done by hand and they produce about 4,000 footballs a day.
the Chinese started using paper in the 9th century
The USA started using nuclear energy in 1951
Old-time basketballs were made of leather (as US footballs are still made), with inflatable bladders inside. However, the laces were eventually eliminated as unnecessary and a problem when dribbling the ball. The move was made to a smooth, spherical ball using an interior air valve, beginning around 1942. (Some photos of old balls are at the related links.)