w8 i thought there were plenty of opportunities for doing charity work and stuff like that, such as MSF (DWB).. surely a lot of the doctors (trainees) go on those expeditions?
Sure, there are those opportunities. But there aren't that many doctors that do that stuff, definitely not as many as you'd think, anyway. And now there's the issue of safety overseas, which you have probably noticed in the news.
Often those doctors aren't the ones driving fancy cars and living in mansions either, it's rare to have both big $$$ and have time for a lot of philanthropy. Having said that, there are many famous (and presumably wealthy) doctors who manage both, but getting to that level of seniority and experience is getting tougher and tougher every year. If you look at someone such as Associate Professor Kate Drummond who I know does a lot of work with Specialists Without Borders, it's very very difficult for someone coming through the ranks to do what she manages to do (full credit to her for being awesome!), let alone even become a neurosurgeon due to the training bottleneck in pretty much ALL specialties (even GPs and psychiatrists!).
If I were a year 11/12 wanting to do medicine, I'd do some serious reading about the job prospects of what you're getting yourself into. I wouldn't rely on what your parents or relatives say if they've been doctors for many years, despite what they may say, it was easier to get 'somewhere' back then. Hence, if you're in it for money, look elsewhere; if you're in it for "power", look elsewhere. You really need to want to do it.