It's the number of transactions not the number of bitcoins in each transaction that takes time.
If BTC costs $50 then 1 BTC is for 5 people. If there are 7,000,000,000 people then we need 1 400 000 000 BTC for breakfast :-)
(but we have only 11,000,000 now, so we must increase in price 50 * 127.3 just for breakfast)