[Would they have learned that lesson without making that mistake? Are you even sure they really wouldn't do the same again?]
It's hard to say. However, I think one really learns the value of money after having been in the work force for a while. I think that experience may have had a positive impact on their decision making had this happened later on in their life.
[To quote Time, "About 70 percent of people who suddenly receive a windfall of cash will lose it within a few years, according to the National Endowment for Financial Education."]
I believe it. But I also believe that the likelyhood of making good financial choices increases with some time spent in the work force. In this case, they had been living a nice lifestyle under their parents when they received the money.
[Just to make the anecdotes match the statistics, I inherented roughly 30k. It remained in my education fund until I finished undergrad. At 22, I opened an investment account. It's been invested in the TSX60 for the past 6 years now.]
You are also on hackernews, a website which consists of generally well-educated people. I'm not trying to sound snotty here, but there's a good chance that you have better judgement than most people.