maybe
(Evil snickering)
By the powers of [punishment]…! I command this particular [bottle] of hot sauce to be
to be really
really
H O T
N U C C H O S
I can see the comparison.
Eh, he’ll grow to like it eventually.
There is nothing wrong with being direct. But a more elegant strategy would have been to booby trap the food. Make him punish himself.
Fluuuuuffffield!
Where is the hamburger helper
his butthole wont
Did that fluff manage to survive? 
The spicy food diet. Add it to all foods and he won’t be able to eat any of it any more.
Poor fluffy. Now the meat is inedible. 
One he’ll get used to it and not want to eat anything without it. Win either way.
Yikes, I’d hope not. The idea is to get him to stop trying to steal food. Might have to lace some trap food with pure capsaicin.
At that point you’d be looking at pepper extracts. IIRC they’re considered food additives to be used in very tiny amounts for very LARGE quantities is something else.