Things you think will make money but don't

A recent Ramit Sethi post began with a simple question: "What are areas where people THINK they're making a lot of money, but actually don't?"

Ramit, who blogs at I Will Teach You To Be Rich, suggested some possible answers: buying a house (hopefully everyone has figured that one out) and picking individual stocks (best not left to amateurs, we think).

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What came next were comments from some very astute readers. Among them:

Buying something for the tax deduction. "Saying you're doing something for the tax deduction is exactly like saying 'I just spent a dollar to save 25 cents!'" reader Erica Douglass said.

Using a rewards credit card. Moneymonk said the person who crows that he earned $600 in rewards/cash back won't necessarily mention that he had to spend $20,000 (or some other amount) to get that reward.

Buying gold. Several of Ramit's readers mentioned this. One of them, Griffin, said: "Without investing, I've seen the price of gold skyrocket and plummet repeatedly. I'm 25." A debate ensued.

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Buying a hybrid car to save money on gas. "Likely purchased by someone who won't keep it long enough (150,000 miles or more) to even break even on the gas savings vs. extra initial cost of a hybrid," Jessica wrote. "GREAT EXAMPLE!!" Kenneth replied.

Quitting a day job to start a business. Entrepreneurship can be a slippery slope. "And in many cases [entrepreneurs] are spending far more than they are bringing in under the aegis of having to spend money to make money," Alexis Martin Neely wrote.

Buying whole life insurance. Baron wrote, "To me, it seems it would be more effective to buy the cheaper term insurance and have the difference in premiums between the whole and term automatically deposited into an investment account."

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"Personal success workshops and investment seminars," Will wrote. Often the only people making money here are the "experts" who put them on.

Think gold was a touchy subject? This one was equally controversial: Cooking meals instead of ordering takeout. "The cost of ingredients, plus the time required, can easily exceed the cost of ordering takeout," Lee Semel wrote, igniting a mini firestorm.

Among those who disagreed, Justin asked: "… would you ACTUALLY spend the hour you saved by not cooking on doing something that ACTUALLY makes you $X? If so, then by all means, order takeout. But it seems to me that for most people, the time saved by not cooking is instead spent on activities that don't generate revenue."

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Going to college/getting an advanced degree. Actually, the problem readers were complaining about was less about the value of an education and more about student loan debt. "I think that college debt will be a defining factor of our generation," Anne predicted. Griffin proposed this approach: Get a double major -- one in a discipline you're interested in and a second in one that will make money.

Do you have a different opinion? Can you add to the list of things people wrongly think are making them money but may very well be doing the opposite?

More from MSN Money:

• Term or permanent life insurance?
• Is eating out cheaper than cooking?
• Should mortgage interest be deductible?
• The costly secrets of hybrid cars
• The $555,000 student loan debt