So why don't you sell on markets?

Hey guys, quick question about swaps.
Let’s say suppose I’m swapping 48 $BTC to USDT at a market price of $96,500 (rounded for easy math). I should be getting around 4,632,000 USDT. But I’ve noticed that the maker fees are insanely high—sometimes around 40,000 to 43,000 USDT—which really eats into the profit.
Is there any way to reduce these fees and receive the full amount?
Also, why does $BTC seem to have different prices on different exchanges? Feels like I'm getting shortchanged depending on where I trade #BTCRebound