I got a really nice toothbrush for Christmas and gave DH my cast off as it was better than the one he was using.
He lost my cast off a couple of months ago and has been using my fancy new one every day since.
I asked him today when he planned on getting himself another one and he said he'd been planning on just using mine! 
I know this is a ridiculous first world problem but aibu to think that's really cheeky? He's drastically reducing the life span of my toothbrush!