I can empathise with your situation, with my brother having just become a dad, but 1pm and 6pm are not particularly bad times to be doing things in the non-new-baby-world.
I guess it's possible that you sounded irritated when you asked the bloke's wife if he could be quiet, which is why she said your baby would have to learn to deal with noise, she might have felt like she'd been put on the defensive?
While eating Chirstmas dinner my brother seemed quite keen to keep jiggling his foot up and down on the bar of my chair while his daughter was on his knee, because he thought it was helping her to be at peace. I did want to ask if he could stop the jiggling and see if his daughter was still at peace because it was a bit irritating, but extended family who i'm not related to were round and I didn't want to seem to be making a fuss, and my brother looked pretty tired and like just wanted a bit of peace, and it stopped being irritating once i'd decided it didn't really matter.
While empathising with how important your new baby is too you, and how important it is that it sleeps so that you can do, not everybody has the same understanding of what the implications may be of what they're doing could be, on new babys which may be trying to get to sleep.
Good luck with your new baby, and I wish it a happy childhood. :o)
Cheers
Tim