If you need to buy a $10,000 watch on credit you should not be buying one in the first place. I can safely assume that people that have $10,000 plus have a iPhone 6 and would use Apple pay at a Apple store.
And anyone interested in buying a $549 plus Apple watch should have upgraded to a iPhone 6 already. If not they need to get their priorities straight.
people who can by the apple watch have credit cards that can handle a 10k purchase. I've charged 8k on my amex before, doesn't mean my priorities weren't straight just meant i do not carry 8k in cash on me.