When loading a singleplayer world, it is counted as a multiplayer game.

Steps to reproduce:
1. Write down the number after "Multiplayer joins" and "saves loaded".
2. Open a singleplayer world.
3. Check the statistics and see that the "saved loaded" hasn't increased, but "Multiplayer joins" did.

I think it's due to that the singleplayer and the multiplayer has been merged together.