[vibrant_mclean]

syncthing automtically connects with bunch of external servers automatically. Relays/discovery servers/stun etc. You can disable but they are enabled by default. They connect on first run and before you get a chance to disable - atleast on android. Everything may be encrypted but I still prefer to not connect to external servers

[candiddevmike]

Yes, IMO the external connections and relays should be disabled by default/opt in for privacy reasons.