Apache license has some language around patent grants that some people want and other people don't like (e.g. apache isn't compatible with GPLv2, some of the BS

Apache license has some language around patent grants that some people want and other people don't like (e.g. apache isn't compatible with GPLv2, some of the BSDs reject it, ... and some people just think its too complicated). Thus offering both makes both sides happy is my guess.