Sorry, but these claims just demonstrate that you have not operated a large volume mail servers.

Yes, most of us do need to automatically block such sources because content analysis does not do a good job, and experience demonstrates that the vast majority of such messages are still spam.

> You're just relying on the provider to solve your spam problem.

Yes, we are. And you should be extremely happy they put in the effort they do, or your e-mail would be completely useless.