I couldn't read all of that without getting bored, but I'm feeling nicer today than I normally would in this situation, so here are the links to everything you need to know. It's genuine knowledge and my genuine opinion follows.
Exchange ActiveSync - Wikipedia, the free encyclopedia
And here is how Gmail works:
IMAP IDLE - Wikipedia, the free encyclopedia
CalDAV - Wikipedia, the free encyclopedia
CardDAV - Wikipedia, the free encyclopedia
I have seen no increase in data usage with the above protocols over BIS, they're as fast or faster than BIS, simpler, and there are fewer points of failure. It's better and far more flexible.
Finally, I absolutely do know the BB market outside of the US. I travel (have been to ~35 countries on 5 continents), and I have lived outside of the US for several years in places a lot more challenging than Indonesia for technology. Don't make assumptions.