The public Bitcoin market trades over 40B per day. A buyer of size can acquire a position w/out big movements in price as long as they're patient. It's more about how quickly they want to get on board and how much slippage they'll accept, rather than their absolute size. Bids and asks are constantly refilling as price moves. Every new level in price drives a pocket of investors to act. You must free yourself from one dimensional thinking in regards to buying and selling.