I suspect that a similar dynamic can be in effect with many industry events. Everyone would collectively perhaps be better off with pulling out of or at least scaling back on big industry shows. But that doesn't mean it makes sense for just you to pull out. (And, certainly, your events team probably isn't going to push for scaling back.)

There's also a huge mutual back-scatching thing going on. I remember in a former life we wanted to pass on a big software vendor's user group show because, while we sort of needed their software for some important customers, we got very little traffic at this expensive event. Their CEO called our CEO and basically said to him "Be a pity if something happened to our partnership."