Meredith has drawn my attention to an interesting discussion on frugality, and Mama Squirrel did me the favor of posting on the personal side of it. Which leaves me more opportunity to lecture on the appalling lack of economic understanding shown by a frightening number of commenters.
Wealth, contrary to the apparent assumptions of many, is not some magical thing that comes down from the sky. Profit is not simply the result of taking things away from other people.
Profit is the wages of a varying combination of labor, insight, hassle, and risk. To take the subject at hand, let us suppose Frugal Shopper goes out and amid the piles of tacky Christmas decorations and battered candle holders at a yard sale finds a Treasure. FS, who pays attention to these things (and that, friends, is work) knows that many people want Treasure and are willing to pay, say $25 for it when it is marked for $5 here at the yard sale. Gasp! A 400% profit! Even an oil company exec might envy that!
Anyway, most of those people who want Treasure do not want to hunt all the yard sales in Ohio for Treasure. That is also work, and it is work most people are unwilling to do. So FS pays $5 for it, takes it home, and posts it on EBay, where people who want Treasure can just type in "Treasure" and see FS's listing. FS, however, is not home free. There are fees and such to be paid. Treasure must be kept around the house until it sells, and then she must bother with going to the post office and shipping it.
And there's always a chance that everybody has all the Treasures they want and the going rate for a Treasure is no longer $25, but $4. In which case FS would be stuck. Also, we have not seen (but FS's sore feet have) all the yard sales she went to at which she found nothing. It may be that FS has made almost nothing, considering all the time and trouble she puts into it, but we'll assume FS is not an idiot and would either stop working if that was the case or enjoys it so much she doesn't care.
In any case, this ghastly 400% profit turns out likely to be a small hourly wage. Middlemen have been beat up on from time immemorial, but they provide a very important service, or they wouldn't exist. They take stuff from the people who have it to the people who want it, when those people don't want to hassle with hunting up the people who have it for themselves.
I, personally, hope I never ever ever have to try to make money from such activity, because I have no talent or interest in it. I have no qualms about paying those who do. They are providing me with something useful.
And they are not taking something away from Poor Person who might have been able to buy Treasure for $5 had they not taken it. That is part of the risks of life. Things are not distributed evenly and they never can be. Nobody is stopping Poor Person from getting up an hour earlier. (And given the glut of material goods our society has, which for some reason the same people who bash profit want to bash, I doubt that Poor Person is without an opportunity to find many other Treasures if she wants to go look from them.)
Now profit can of course be theft, just like wages could be. If you don't do your job, taking your paycheck is theft. And if you lie or cheat or steal to make a profit, your profit is theft. But (given how other people feel about being cheated) profits are much more likely to be an expression of how valuable the activity you do is to other people. And what's wrong with that?