Grandpa Joe was a useless lazy bastard
Bedridden for 20 years making his family work while he lies there doing nothing, Charlie's mom worked numerous jobs to feed the family and as soon as Charlie finds the golden ticket and gets a free ride to the factory Grandpa Joe miraculously has no muscle atrophy or bed sores from crapping and pissing himself and does a full dance number.
He should have been brought to trial at Nuremberg for crimes against the state.