The thing is, in other countries we are the foreigners. I think its quite rude not to adapt to the culture and their way of life here which is why we try to "fit in".
And also, to be honest, I would actually prefer to speak English while I'm here just because I don't want to offend anyone who doesn't speak my language. I don't want them thinking that I'm talking bad behind their back. And ultimately, it's just logical to speak English in an English-speaking country.
(Although, if I'm sure that everyone in the room can understand me if I speak my native language, I am more than happy to do so. I love my language.)
What's funny is, the Filipinos who group together with other Filipinos are the ones that are more ....liberated. This doesn't go for ALL of us, though. I guess this is just my biased opinion, because everytime I join a "Filipino gathering", I always feel out of place. I just cannot relate to any of them at all.