One possible problem I see is that females becoming comparatively "irresponsible" about birth control due to perception of males having vasectomy, which may increase accidental pregnancies. I am not taking birth control methods used for STD protection into account here, but the the award of 10k may need to be carefully set so as to have an optimal ratio of infertile vs fertile males. Seems like an interesting proposal though.
And what if a human female "gets off" on the ejaculation???
This is the point I'm making... you are asking that human females satisfy themselves with that which YOU deem it acceptable to provide them. What happens if a human female, indeed many human females, decide they want something different???