I can get it for some environments. For example in central Asia, coming from a nomadic lifestyle and living in yurts (big tents) it's totally understandable to keep your shoes on. Maybe the building style is a continuation of the yurt and lends to similar choices.
I was once in Paraguay and their buildings typically don't have a hallway, every room is accessible from the outside. Most of their life is also spent outside, like cooking and eating. It's nice weather for most of the year, why not.
But for European style weather and houses, I will always take my shoes off.
I think, if your savings can't cover your basic needs for a month, you're in it. If you miss one paycheck, your life basically falls apart. It also means, if you have a sudden cost (car repair, water pipe burst, or illness in the USA) that is more than a monthly paycheck (which in turn is more than your savings), you're done.