Brake Drum Hub Assembly Mystery

The whole swedging process for these hubs never made sense to me anyway.
I am sure there is an engineering reason for it, but if the studs are pressed into the hub and then the studs are bolted to wheels on the car, the wheel and drum are not going anywhere, even with the added braking heat. If they did your wheels would fall off too, loosing 5 lug nuts and studs in the process.

Many other processes just press on knurled studs and slide the brake drum / rotor over the studs then bolt on the wheel to make a hub flange / drum or rotor / wheel mechanical sandwich.

Maybe it was for hub to Brake drum balance? But if you replaced the brake drum it would be (likely) out of balance again.