Yep. Good post. I don't have a problem if for instance two Indians or Sudanese etc are chatting away together in their native tongue. It would be the same if I was in a non english speaking country and we met up and started to chat, we would naturally speak english.
If I wanted to interact with the locals then I would try to use their language. It's far more easier these days with the myriad of translating/translation apps going around.
Totally agree, yet I feel native English speakers (I am one) are probably the most arrogant people in the world. We expect everyone to who comes to our countries to speak English, and yet when we travel overseas we expect people to speak English everywhere we go.
One thing that does make me angry though is when shops and restaurants in Australia only use foreign language writing without accompanying English translations. In my experience this predominantly occurs with Chinese.