I don't think i've ever met a client who neither knows or cares what lot the pilots are on - and this will never change. If such a person does exist then they are in the minority. I'm almost offended that you seem to think that there are companies operating who have made fiscal decisions that dimish safety. Those that were caught doing this lost their operating certificates a long time ago and - in the UK at least - are regularly audited by the governing body to ensure this doesn't happen.
I think that you should put that quote in "Friday Jokes" in Jet Blast...