I have done in the past, with stuff that was going to be recycled anyway: slice the spine right off with a knife and a steel rule, dump the pages in the ADF, hit go and wait a few minutes. It's ace, I love it.
*But*... some mags, like ETI, aren't really "bound." They're just folded in half and stapled, one giant signature - so there's no real "spine" to cut off. I've thought about flattening it and slicing through the middle, but I'd worry the remaining curve would jam the ADF...