I am flying to the states so a 5 hr train ride then in the airport for 4 hrs then when i land another 8 hrs train and then a hotel for 14 days and will be using wifi differnet ones how do i know if anyone else has used these servers for the game i know it says shared connections
You should be okay on a train/plane/hotel as there aren't a huge number of people sharing the WiFi with you (so the chances of a TW player on the .net server and same world on the same journey at the same time are very low). You would almost certainly know them and were meeting up with them if that happens.
Shopping centres and other places that have hundreds/thousands using a shared WiFi add a tiny bit of risk but still very low.
Short of asking every person you meet, "hey do you play TW", you wouldn't actually know who is on the same WiFi that plays the same game as you.