Scavenging whippet

[CrazyPuppy]

Hoping for some ideas or advice. Our 2 yo whippet is a delightful boy in all respects except one. He is a terrible scavenger.

At home, his thievery is relatively easy to keep under control with constant vigilance, but out on walks it is becoming a real problem. We live in a city so come across dropped scraps and bits of edible (and inedible) junk quite frequently. Ddog is well fed on Millie's and various treats but he literally can't resist the lure of disgusting rubbish. He is sneaky about it too, and will merrily charge off ignoring me if he thinks there is a chance of scoffing something unsuitable. Even when walked in the woods or on the beach he still manages to find weird things to consume.

He knows "drop it" and his recall has always been good but the scavenging is making me nervous to let him off-lead. I'm not keen on the idea of a muzzle but worried about him swallowing things he shouldn't. Any ideas oh wise ones?

My sisters whippet is the same will eat anything he finds he's a nightmare.
While out he's eaten anything from disguarded take away to dead rotting animals - birds, mice and a rabbit and his personal favorite grass snake. ( he's also tried to eat a dead budgie.)
Indoors he's just as bad and constantly gets in the bin and has even eaten the containce of dirty nappies.
Nothing stops him she just has to keep her eye on him as she too doesn't like the idea of muzzleing him.

Oh dear. All very familiar. Discarded takeaway - check. Contents of cat's litter tray - check. Last week he delighted us by sicking up a whole crab! Makes me feel slightly better to know ours is not the only walking bin though!