There's a thing called lifestyle creep. You may not necessarily be living paycheck to paycheck on the bare minimum. Going out with friends, having the latest phone, having hobbies, if you cut out all fun you may be able to save up significantly. You can also live like a bum in the least accommodating space you can stand. Being comfortable is expensive, but not everybody wants to be uncomfortable for long stretches just to fuck off to the Bahamas for a month every few years. That or credit card debt.