Why strangers follow you on Twitter:
If someone follows you on Twitter, they will appear in your followers’ list, can view your tweets in their timeline and are able to start a private conversation with you.
People follow those they do not know because they may admire and connect with your intellect, wish to start a debate or may simply find you funny.
Random people may also follow you just to receive a follow in return.
More followers means more visibility ... Read even more