I hate to open this can of worms, but there is no reason why libraries cannot make the copies. We allow up to two copies shelved behind the desk and up two copies in self-service file cabinets. This is our own intepretation of fair use. The law does not stipulate number of copies.
Libraries can make the photocopies, faculty can make the photocopies.
There are no hard and fast rules. We must use our judgment, and allow the faculty to use their judgment.