What do you do when a Conference is poor?

I rarely go to a Conference these days. They are usually expensive and difficult to gauge what benefits will be gained by attending. The Conference in Glasgow yesterday - "Enterprising Scotland: Challenging Times" was just that. DVD's to replace keynote speakers is not acceptable as are poor presentations and lacklustre peformances. An empty slot "due to snow" is a lame excuse in Scotland in February - especially with no stand in. As usual with these events there is the chance to catch up with colleagues and chums which was good, especially over an acceptable buffet. I now have to decide whether or not to send in my scathing evaluation form!