You can enter the competition, just join Facebook. It is your choice not to want to join Facebook, not the companies. It is a little bike like complaining that you cannot buy a Carerra bike because you refuse to shop in
Halfords.
Regarding social media, try the dictionary definition.
Definition of social media
: forms of electronic communication (such as websites for social networking and microblogging) through which users create online communities to share information, ideas, personal messages, and other content (such as videos)
Or if you want try wikipedia
"marketing and social media experts broadly agree that social media includes the following 13 types of social media:
blogs,
business networks, collaborative projects,
enterprise social networks,
forums,
microblogs,
photo sharing,
products/services review,
social bookmarking,
social gaming,
social networks,
video sharing, and
virtual worlds.
[18]"