Raising ferals

Advise wanted please. My husband and I have been together for almost 16 years and have 4 kids together. My issue is my husband completely contradicts the things we're trying to teach our kids. For example, we are constantly telling our four year old to eat using his fork/spoon, not his hands. We are both agree and we are both telling our son this but right after my husband says this to our son, he picks up a peice of food with his hands and puts it in his mouth while my son watches. Our kids are doing as we do, not as we say. And fair enough too, we are their role models!
There are so many examples of this like going outside with just socks on, leaving dirty clothes on the floor, putting dishes in the sink, eating with their mouth open, talking with their mouth full, burping at the table, eating while walking around . . . . . The list can go on forever! I don't think this is something that my husband does on purpose, it's thoughtless habits. I have tried telling him quietly away from the kids, not to undermine him with no success. I've said it in front of the kids; first thing was ok, but with each one I mentioned, he got more offended. I have tried to drop subtle hints with very little effect. And on the odd occasion he hears what I'm trying to say, he'll change his habits for a day or two (tops!) then slip back into his old habits.
To add to it, when I'm constantly having to remind him, I feel like I'm raising a fith child and is beginning to do damage to our relationship. I also think that this is really unfair in the kids being hypocritically told off all the time.

And before the 'your being too up tight' comments come, I'm not. I would let at least half of the things I notice go.

I'm ready to give up and let the lot of them do what they want and have zero manners.
Any advice?
Thanks in advance.