Why then do you guys repeatedly keep thumping your book at such people, if scripture plainly says they won't get it?!

Logic would suggest that if people are not going to buy your doctrine or whatever because their hearts are supposedly unreceptive to it, we'd be better off emitting things they can receive - kindness, respect, etc. - instead of beating the dead horse trying to force a square peg up their hole.

It's a matter of flesh vs. spirit. Fleshly, carnal evangelization will always fall short. Usually this comes from "believers" who really don't trust God to do His thing, so they take it upon themselves to try and convert the wicked heathen evil-doers with a lot of arm-twisting.