While there is an increasing amount of data available for free via the Internet, and everyone likes 'free stuff', there may be times when you would be better off spending a little money and getting the data on a permanent storage media.
Some offices have just one Internet phone connection, or perhaps have poor quality phone lines.
A permanent storage media like a CD-ROM disc also gives you a good archive copy of the data. The USGS Earth Science Information Centers, located around the country, distribute much of this data on CD-ROM's. They are also a good source of information on precisely which data is available at any given time for your geographic location. Since the availability of digital data changes constantly, it's good to be able to get up to date information.