> Spending money you don't have is being financially irresponsible, regardless of whether it's through credit cards or some other equivalent.

Meh - I've spent money I didn't have when I was younger - life is short, what was a lot of money back then is irrelevant to me now and that's expected (you earn more the further you go in your career). I can't go back to twenties now no matter how much I saved back then.