Your argument is very weak. The picture you've shared is at least two decades old at this point. And people showing their asscracks can also happen with suits,

Your argument is very weak. The picture you've shared is at least two decades old at this point. And people showing their asscracks can also happen with suits, especially if someone is not used to wearing a suit often (e.g. it's not perfectly fit to their body shape). On top of that if organizers are hoarding hundreds of people in what looks like a multi-purpose location on the cheapest chairs/tables possible, then why should these people who need to sit and concentrate for many hours be forced to do it in expensive/rarely-used clothing.