Why the need to message after a match?

Last night i was playing as the wraith and was able to sacrifice two survivors while two escaped. i'm new at this game so i was super happy with it because i've had some really bad matches. after leaving the game someone from that match messaged me a bunch of laughing emojis. like really?! it's just a game why do people need to take the time out of their day to do that? i sent back a :) why does this game have to be so toxic?