For non Shopify Plus users, you cannot modify the checkout process, and this means customers can add their name & address in any format they wish. Some customers will use all lowercase, others all uppercase, and the really annoying one, a mixture of cases. There is no automated way to catch this, you have to wait until you go to fulfil and realise the address label looks messy and needs retyping, opening up the possibility for mistakes, taking your precious time, and ultimately costing money.