"Doing Business" at poker rooms

[arod15]

I was at a room in NYC the other day. There was a huge pot in the middle but before they flipped a guys told the other guy "Do you want to do business?" The other guy said well i have the straight so i dont know the other guy flips over two pair with one card to go. THe guy agreed to "Do buisnes" so the fliped the river the guy boated up. Then they did another river which was a blank and another river which was a blank. So the guy with the striaght, won 2out3 pots and won 2/3 of the pot. Is this common? Is it worth it EV wise?