Stinking behaviour

Following a good day at work, my mood soon soured when I arrived home to find that our household waste wheelie bin had dog shit in it again!!!

Our bin is emptied every other week, so 2 weeks ago when it was last put out for collection, I noticed it was a bit whiffy so thought I'd clean it out once it had been emptied.
No wonder it was whiffy, as stuck to the bottom of the bin was a little black plastic bag, tied at the top, full of dog shit!

This was removed and disposed of properly and I bleached the bin clean.

I don't know what made me look today, but I did as I wheeled the bin back up the drive. This time, a tesco bag, tied at the top again full of muck which absolutely reeked!

Our close doesn't get passing traffic and it's certainly not somewhere where people regularly walk their dogs (especially since the park is just over the road), so we have our suspicions where it might be from, but sadly no proof.

I'm not a dog owner, but really don't know who would put this in a household waste bin; let alone in someone else's!
It disgusts me.

For obvious reasons, I didn't want to blip a bag of poop, so instead you have our lovely rhododendron's - left and right sides of the garden.