I'm Canadian. You wouldn't think that would be very different from the U.S., but... when I first visited the U.S. as an adult (Boston), I had to change my gait IMMEDIATELY. I was a fast walker, and had been trained as an actor to hit toe first "for better energy" - that is, to appear more energetic on stage. Trouble is, that makes you quieter, and Americans in the Eastern US back then simply assumed that anyone gaining on them quickly and quietly from behind was probably a mugger. Pedestrian after pedestrian after pedestrian would whirl around to look at me in a startled way, even during the day, nevermind at night. So I learned to thump my heels down noisily for my stay and that eliminated the problem. I could walk fast without frightening anybody, as long as I was conspicuously loud about it.

Noisily thumping along is also a way to get people who are walking slower and blocking your path on busy Boston-area sidewalks to notice your presence and move out of the way.

I kick gravel or scrape the ground with my shoe every once in a while at night to make my presence known.

Have you noticed others scuffing their shoes in response? I do. I'm almost sure it's some kind of unconscious communication going on.

Maybe there is something similar with coughing. There definitely is with yawning.

No I haven't.

I wouldn't think you were a mugger, it's just startling when there's suddenly someone behind/next to you when you thought you were alone.

Yet Canadians weren't startled at all by the same walking style at that time - or so rarely I'd never noticed.

That’s a great cultural example.

Gait and personal spaces are strange cultural artefacts. I can even tell if someone is from a large city like Delhi in India or a small town based on how fast they walk and how tolerant they are of others encroaching their personal space

Is this cultural or just environmental e.g. better roads, less rubbish, less crowded street?

It can also be gendered; a strong signal of male/female (or at least masculine / feminine) is in the gait. Men walk with their shoulders, women with their hips.

Male/Female this is due to the pelvic structure.

Nope; it’s not. Totally social. Ask any trans person; I know many and this has come up in the past.

It’s not social at all, transexuals can attempt to mimic this but your precession is dependent on your pelvic structure.

Any forensic or surveillance grade gait analysis software can easily distinguish between the sexes and it’s not fooled by sex reassignment operations or sexual orientation.

I am very skeptical of this claim. There is enough variation between individuals of either gender to make positive identification close to impossible (not to mention that muscular / ligament changes in the hips on hormones can cause the hips to rotate over time into a different position). Sexual dimorphism in humans has such significant overlap and grey area that positive identification from physical characteristics alone is going to have a significant error rate.

Interesting! Another way you can tell it's cultural is that the running community does both kinds of gait. I'd never noticed Indians toe-walking, but I do meet recent immigrants from India on a regular basis, so I'll have to watch for this in the future.

Could you elaborate on this? What precisely is the difference?

Rigid shoes are not strictly “better”. Arguably they are in many ways worse, stunting development of small stabilizer muscles throughout the foot and lower leg (through disuse), reducing flexibility and dexterity, encouraging poor posture, and leading to various kinds of injuries especially among runners (heel-striking when running puts a lot of repetitive shock on all of the hard tissues from the heel up through the hip, even when wearing very padded shoes). Shoes with even slightly raised heels in particular lead to reduced ankle flexibility, which impairs squatting and jumping (this is compounded by a lifetime of sitting on European-style chairs for hours every day). They also tend to not be very foot-shaped, causing blisters and cramping people’s toes inward: adults in rigid-shoe-wearing places end up with really weird shaped feet, bunions, etc., sometimes requiring surgery to fix. I suspect that many mobility problems among the elderly are caused or exacerbated by a lifetime of wearing rigid shoes. Maybe less importantly, they lead to much louder footfalls.

Their main advantages are (a) they are more waterproof, (b) they are more durable (especially on hard rough surfaces canvas or thin leather shoes wear out quite quickly), (c) they offer some protection against sharp objects that you otherwise have to pay more attention not to step on.

TL;DR: Wearing flat shoes fixed my feet.

My orthopedic doctor had me switch from arches and heels (typical running and dress shoes) to flat souls and minimal pressure on the back of my heel (flip flops, Keen sandals, those thin shoes from New Balance). It both helped clear my plantar fasciitis and my flat feet got some arches.