I hear some trick from people, they buy coin when binance listing rumour heared, they buy it on another market which list that coin too.
Just before the listing happens, sell some percentage of the coins (if the price already high) and send the last coins to the Binance to hold for a short time (because sometimes theres another pump).
Not unless it's only listed on Binance first.
But if it's also available in other markets, that's what they really do. Those traders that have been following listings on Binance are very active and quick to research which exchanges has that coin and they'll buy it.
After buying, they'll wait for the official listing on Binance and will send the coin there which is about to be dumped with a higher price.