natural selection also applies to memes. memes that cause their host to fail to raise children to reproductive age will get weeded out, but it can take many generations.
Memes don't need to be passed on hereditarily. It is entirely possible for a meme which absolutely prevents the host from reproducing to persist indefinitely so long as it spreads to new hosts at around the same rate hosts die out. See clerical celibacy. It is also possible for memes to lie dormant and then resurge after an extended period of time by which all the original hosts are dead.