I make icons myself and it annoys me when other people take them and claim them to be their own.

That is just wrong to claim your work as their own.

What I find off-putting is the hyper-sensitivity of some icon makers about their own work and no crediting of original artists. I know more artists better than I know icon-makers, so I am sure that influences me. I know a few artists who do not want their work cropped. It's like mutilating their baby to them.

I only recently began to occasionally use other people's icons (and I do credit). I found the makers terrifying and they rarely credit artists.

I have a few non-credited sources of original art on my own icons. But after encountering such complicated rules over people's screen caps that I though it would be better to do my own.