Totally. Grapes won over my uncle's mean rooster.

Foil won't stop a raccoon though.

On my street, several fences failed after heavy rains because posts were set wrong. Your gravel and sleeve method is exactly the kind of simple fix that gets overlooked for fancier solutions. I see this all the time, where the basic approach ends up being the best.

Honestly, calling interference 'drives me nuts' seems a bit much for just a flickering picture.

Have you considered chilled rice might be better for handling? Cold rice sticks together more when shaping nigiri, so it doesn't crumble in your fingers. I've been to places that chill their rice and the texture stays firm from kitchen to table. Warm rice can make the nori chewy and ruin the snap of a good roll. Chilling helps if you're making lots ahead for a party. Letting it sit out just makes it go stale faster.