I would thing that a few drops of pure capsaicin, rubbed into the leather, would fix the tendency.
I suggested regular Tabasco sauce to my wife a few months ago when he took apart her slippers and two pair of flip-flops but she nixed the idea because, “We don’t want to hurt him, he’s just a baby and will grow out of it.”
She also lost a twenty year old pair of winter boots about three weeks ago, haha!..