Pink flowers are typical of S. purpurea subsp. venosa var burkii. I believe that's why some want to assign the species epithet "rosea".
Notes from Barry Rice's FAQ on Sarracenia rosea (as Barry Rice accepts the new name):
Note also:2)Sarracenia rosea is the only Sarracenia with pink petals (except for some hybrids). The petals of S. purpurea are brick red to purplish red.
http://www.sarracenia.com/faq/faq5542.htmlSarracenia rosea plants from the Chipola (Florida) area are particularly cute, and often have fat little pot bellies.