I saw them as a legit fan (during an embarrassing phase.) It was one of the worst things I've ever seen. This was in Manchester, and if I recall correctly, their Manchester performance is pretty infamous now (for good reason. I'd be legitimately amazed if they're allowed back at the venue.)
They brought some disabled guy in a wheelchair up on stage, joked about how the guy's testicles don't work. The music was so loud that you could barely hear their voices (maybe for the better, now that I think about it.) They had a violinist on stage who would mime playing violin even on songs that didn't have a synth violin in them, since all their instrumentals are electronic. Actually, come to think of it, there were about four superfluous roadies on stage all times - the band is only two people rapping and singing over premade instrumentals, but they had a group of six on stage at all time.
To cap it all off, Dahvie flashed his hairy ass and balls, and held a foam cannon between his legs to imitate jizzing on an audience of almost exclusively teenage girls. Also, they made fun of the supporting band, a BOTDF ripoff who were frankly better than BOTDF solely for the fact that their members probably weren't rapists. Jayy threw his stretched-ear jewellery into the audience. Apparently, teenage scene girls like nothing more than to have some guy's crusty ear jewellery and to see a 30-year-old Mexican man's taint.
I met Dahvie after the show, and he was inviting random teen girls into his trailer. Made my friend wait while I met this Dahvie douchebag too. I honestly want to go back in time to that moment and beat the fuck out of my 16-year-old self for that :/