Shouldn't wifi be "langaton netti", not just "netti"? There are still other possibilities to wireless internet in use, so netti shouldn't be translated to just wifi or the other way around.
Yeah, there's definitely a difference. Precisely WiFi in Finnish would be langaton verkko, not langaton netti.
Miksi ette halua or Miksi sinä et halua, both should be correct!
"Miksi (sinä) et halua...?"
"Miksi (te) ette halua...?"
Wifi is commonly called Wifi also in Finnish. It does not mean 'netti', which is the whole connection.