The Internet can cost alot- or a little. Most Internet Service Providers are low cost (between 10 and 20 dollars a month), but these are for 56k users, and this isn't very fast. High-Speed Internet can cost 30-50 dollars a month, however it is much faster than 56k and is always on.

Along with that there are always people shopping online, especially during holidays to beat store rushes. Most internet users have bought something online and continue to do so through regular sites and through auction sites like Ebay. People spend billions of dollars a year online shopping (and even more on shipping).