http://www.istockphoto.com/help/licenses
I wouldn't be surprised if this kind of restriction is common in most stock photo sites.
Dreamstime: http://www.dreamstime.com/terms#unauthorized Apparently you can use it in a logo, but you cannot trademark it- which resolves the problem of someone trademarking it and suing you- their trademark would be infringing the license.
123rf: http://www.123rf.com/license.php?type=enhanced
Yes, this license does forbid use on logos, so that designer apparently did indeed violate the license. The designer should have read the fine print.
Freelancer: I couldn't find terms for stock work, however, the headline in the screenshot is "travel agency logo" so based on that, it appears it is meant to be a stock logo.
So, it appears that 2 out of 3 of the sites do allow us of their artwork in logos. It may not be a good idea, but in these 2 cases, I would not call it stealing. Nor would I expect anything more for 5 bucks.
I don't know if designers get more angry at people who take logos constructed out of stock parts in this way and use them or at the people who supply those logos. There are lots and lots of them out there.
Even at just above minimum wage, wouldn't the time this person spent communicating with you about your company consume at least $5 of wages, before any actual graphical work began?
At the very least I'd hope $5 worth of thought went into it before $5 worth of actual drawing work commenced.
In other news oh my god my $5 shoes fell apart.
The point is that doing some kind of fast creative work is physically possible. You can even get quality creative work for a few dollars. Go find a street artist.