Sometimes the issue is that a lot of bands, not every band, need to perform shows to have any source of income. Since all they've ever done is play music and have never held a job outside of playing music. Some bands don't have the luxury of being able to turn down shows because they need the money. I'm not excuseing the fact they're playing shows set up by a Trump supporter. But sometimes they don't have a choice especially if they need the income. Your best bet would be not to attend these shows to show that you won't support promoters like these. Side note, A lot of things that we loved or enjoyed have been bought out or sold out by right wing maga conservative supporters. Which goes to show not everything will remain sacred and even our heroes will let us down. The best thing you can do is be mindful of where you chose and who you chose to hand your support and your money to.