Too Much Spam with Yahoo

I don't get it. Once a place gets your email address, what difference does it make what email server you have. If they send an email to an email address, its going to go there, no matter what it is. Who are you "yahoo" haters trying to BS?
Or are you just talking one spam filter being better than the next ? Get real, if a filter gets too tight...or selective, it will start spamming the good mail, DUH !