With the increasing threats and penalties that were levied to sites that inter-linked from the same C-class IP addresses, companies started to hire C-class space from different IP addresses to host their sites, so that it looks as if their sites are hosted from different and varying IP address.
Taking advantage of this requirement, many companies came up with web hosting and SEO hosting services. These companies sell you entirely different sets of C-class IP Addresses, which companies use to hide their blog pool or inter-linking network address. Opting for C Class Hosting is like a mask to your original identity.
But remember that Google is capable of viewing all the contact information of all your domains, so it will be pointless if you use the same contact info for all your domains. Doing this will spoil all your efforts of spending money for purchase of C-class IP addresses from SEO hosting companies.