So, here are the choices:
1. Save thousands of people from having to deal with multiple spams per day,
at the cost of presenting a minor inconvenience to a few, or
2. Require thousands of people to receive and deal with spam (or to learn
all about mail filtering), in order to avoid inconveniencing a few.
Easy decision to make. For every bit of whining by the usual suspects,
there are thousands of folks that are very happy to have the spam kept out
of their mailbox automatically. (Every mailing list manager knows that the
whining by Keith and Lloyd is nothing compared to the whining by the list
members as they get spammed multiple times per day.)
Indeed, this is a lot like the arguments re NAT. There are the thousands of
people it helps, vs. the few who are yelling that the sky will fall if it is
not stamped out.