Erm... Under John Brown (the CEO of BP up until, oh, '06 or so), BP was interested in (at least presenting the image of) being "green". The current CEO is an axeman, and most of the programs he cut were "non-traditional energy". (Also, safety programs. Which is why the number of safety violations BP has gotten tagged for has gone up exponentially over the last few years.)

And if you need to justify buying the stock, Scott Adams (of Dilbert fame) had a nifty blog post on the wisdom of buying stock in companies you hate.