Not to be a d!ck, but I think it's for multiple reasons and these are not listed to me, in order of importance.
1 - New ownership. NBA realizes it got lucky that someone actually bought this sorry excuse for an NBA team and was probably going to reward said owner with an ASG before 2020 anyways, it also could have been part of the actual deal to BUY the team that New Orleans gets to host the ASG within the next few years.
2 - NBA feels bad for New Orleans. I could give 2 craps about natural disasters, they happen all the time and people losing lives, their homes everything etc. to me is just the risk of us living our day to day lives. A tornado could hit where I live, snow storms could devastate others, hurricanes, monsoons, electrical storms etc. but I think the NBA wants to help generate money in the New Orleans area as they are still trying to get back on their feet after Hurricane Katrina, and lets face facts New Orleans itself is always affected by tropical storms and being a city below sea level doesn't help.
3 - New Orleans is probably going to be getting a top 3-5 pick this season and next season, both of which could be great players. Both of these players, along with the other draft pick they get from US, could all be on the Rookie / Sophomore teams to showcase the Hornets, which would give them publicity and notoriety.
4 - This could go along with point 1, but the Hornets made a deal with New Orleans to stay in their current arena until 2024, which means no team to Seattle, Kansas City, St Louis, Anaheim etc ( at least not the Hornets ). As a reward and for keeping their franchise, I think NBA executives or whoever makes the decision on where the ASG will take place, probably factored this into the equation and rewarded them with another ASG.
5 - New Orleans is a good weather / tourist place to go during the cold months of the year. Much more revenue can be earned for the city as thousands will head down there anyways for vacations, but thousands more could go down there, not get a ticket to the game but wanna go down there simply to be part of the NBA ASG weekend atmosphere. This means more NBA apparel sales, more revenue generated for businesses. And the weather part helps as well, would you spend more money in New Orleans, Miami, Orlando etc. when it is warmer out, or would you spend more money in Chicago, New York etc when it's got snow everywhere and potentially anywhere from 10-35 degrees out? I think I made my point.
IMO Oklahoma City, San Antonio, Portland, Detroit, Chicago, Brooklyn ( Nets when they get their new stadium ), Bobcats and Minnesota all need an ASG. Not all the teams on that list are good or are great tourist locations, but the fact is certain cities do deserve and ASG and certain teams / cities NEED the revenue.