i dun see any use of stealing opponent permanents
and then returning them except weapons and shields
There are plenty of situations you could use this card, it doesn't just have to be weapons and shields.
If they have an Unstable Gas, you could steal it and (assuming upped) not let them use it.
Same with Hourglasses and SoG, even in the unupped form, they can be stolen and used (although HG probably means you'd have to have a weird Darkness rainbow).
You can ruin SoP OTKs and essentially steal Cloaks and Dims for only one
rather than four
That's just a few, there are a lot more situations when stealing then giving back/destroying it is useful.