I'd still consider it grounded on reality, with the flair of a pro-am game it changes it up, they're not as likely going to play like a strict NBA player cranking out a W... In real life most of these pros take an opportunity to show off and have a bit more flair, like KD dropping 66 points with 4 straight 3pt shots because he was feeling a flow in Rucker.
Even Nate can still get to the rim, he just doesn't do it nearly as often in a real NBA game, but if he was playing in a pro-am he'd be a bit more flashier. Go watch some pro-am highlights to get for an idea of what I'm referring towards -- going from the NBA to a street court brings on a different mindset for a number of these guys more often than not.
It's not always about getting a W, it's sometimes about making a statement (see Vince Carter in Rucker), or doing it for a good cause and giving back to the community you love (see Jamal Crawford at the Seattle Pro AM).
Edit: I suppose I should also mention most of these attributes we used the NBA version as a base with relatively minor tweaks here and there. So they'll still shoot like you see in tip-off, but they might play onto their strengths or what the crowd would want to see from these pros in a Pro AM environment. A lot of these dudes were actually not even touched.