If it's a CL game there is a chance of an ex player being in the Museum. Against Manchester it was Elber, and against Gala Sergio. However, the last entry for the Museum is usually around 17:30.
I went there during the Manchester game, and Elber showed up around 18:30. So if you have the time, and want to take a picture, and get an Autogramm, it might be the perfect opportunity.
There is usually a post on the website who will be there, and more info.
Download the Allianz Arena App. You can order food and drinks through it. It will ask you for your Block, after you pick the one you are in, it will suggest you the closest Kiosks. You still have to pick it up yourself, but the line is much shorter, the vast majority doesn't border with pick up.