Couple of things to note:
1) The contraceptive pill doesn't *just* stop women from getting pregnant. Many women take it as it makes their periods less painful and shorter. Ergo the pill has a multi-faceted purpose.
2) If you (and I don't just mean the OP) believe that men shouldn't help cover the pill because it's not their responsibility, then they should stop having sex with women who aren't on the pill. There's a reason why women take men to court to help pay for the children those men helped to create. If you can't do the time, don't do the crime.