Both include Punkbuster and Gamespy, but you can just cancel the installation for both, if you only intend to play it singleplayer. To stop the Gamespy installation from starting on every launch just delete the Gamespy folder from your Crysis/Crysis Warhead folder.
Additionally both have a 5 machine limit, which can’t be revoked and reports state, that even if you contact EA, they won’t give you extra installs (for the Steam versions), when the limit is reached.

According to multiple forum posts Crysis dosen’t have an activation limit on Steam, Warhead can be revoked but can be buggy with that.