All of us - even those with a very poor grip of fashion - have an awareness of what kind of outfit is appropriate in certain environments. You don't turn up at a wedding wearing a white dress unless you're the bride, for example. You almost certainly wouldn't turn up at work in pajamas. They're a little more relaxed about the dress code in Disney vacation resorts, but I still wouldn't suggest this t-shirt.
For those who aren't in the know, Deadmau5 is a Canadian DJ who makes house music, and his name is pronounced 'dead mouse.' This man could probably have got away with a shirt that just said his name, but the array of dead mouse skulls with Mickey ears around the logo are a step too far. Now look what's happened - he's made Minnie Mouse cry!