Because they had a problem and they wanted a solution. It's basically "blackwashing" and BLMGNF (good night funds?) was there to "sell" them the solution to a problem they were facing.

There's basically zero desire to actually really work on any problem that isn't related to their stock portfolio, so they jump at it and post some PR and then they're done.

Happens time and time again, more or less legit depending. Look up donations to environmental groups whilst the business doesn't change much if anything about what they do.