Why else would anyone ask how to do something if they weren't going to use the code offered (at least as a guideline)? And why would anyone post code if they were only going to object to it being used.......
End of story. The point of posting code is not to say "this is how I do it and so I forbid anyone else from using the same method". Just give credit where it's due.
Copying is the sincerest form of flattery.
Passing other peoples work off as your own is just plain sad.