I wonder how people at their own home would react if a guest put their bare feet/with socks/with shoes/whatever on their coffee table. Great place to stretch out and make use of available space it seems. Stuffed if I'd let them in my place again.
Guests at our house are welcome to put their feet up - and do, as do we - although I must say not with shoes on. But we're generally a take-your-shoes-off house.
Feet are for floors. It's their natural habitat.
So I'm guessing you spend each night sleeping with both legs hanging out the side of your bed and both feet on the ground?
Sitting with your feet on the floor for 12+ hours in cramped conditions on a long-haul flight is clearly NOT a "natural" position for a human - which is why, given a bulk head, my shoes are going to be off, and my feet are going to be on it.
I personally wouldn't put my feet on an arm rest, that's someone else's space and I think it would be intrusive.
But no-one from the anti-feet-on-bulkheads camp has explained just exactly how someone having their feet up on the bulkhead actually affects them. All the other behaviours described - reading newspapers on trains, feet on someone's arm rest, sprawling around outside your own space, etc - have an actual physical effect on someone else. Putting your feet on the bulkhead doesn't. It's analogous to someone wearing pants you don't like, or painting their living room hot pink - you might not like the look of it, but it simply doesn't affect you at all.
So I fail to see - and no-one has demonstrated - just how this behaviour can be characterised as "inconsiderate".