After reading the article, the anger goes away slightly from the chickbait shock of the title.
They are not seeking money but instead filing to seek if they are indeed liable for suit from the victims.
I disagree that it's judge shopping. I think they are being smart by taking it to federal court as to ensure that they get a proper country wide ruling based on the fact that this will and can happen again in the future to other businesses across the country.
There is already law and acted that says if a company takes "terrorist" precautions then they would not be able to be held liable and since MGM hired a company that is certified with Homeland I believe, Then they should be exempt as well. Which kind of makes sense when you think about it.
So instead of having the victims sue MGM in about a state court, where they then bring the federal law of exemption into a account, further delaying the case, and taking it all the way to federal court anyways maybe 5-10 years down the line, playing this now just gets it out-of-the-way now so everybody knows exactly what's going on without wasting time. I think that's a much better for the victims.