Uh-oh... Horses getting into stuff

I know it aint mini related but...today while I was busy dying warriors mane Voodoo got into a kilo of livamol and ate the hole lot.
He always does things when he knows my back is turned or im inside
It was it a tightly sealed container up high but still he manged to get it and eat it 0_o...Should I be worried?
Im so over it he ransacks everything he opens feed drums,pulls old chaff bags out ect ect he gets fed and he aint hungry he just wants to eat all the friggen time! I swear i am banishing him to the grass-less paddock by himself forever.