No, it isn't. As organizer of http://scaleconf.org/ http://scaleconf.org/ I can tell you that almost all of the money goes towards venue hire, lunch/coffee/day

No, it isn't. As organizer of http://scaleconf.org/ http://scaleconf.org/ I can tell you that almost all of the money goes towards venue hire, lunch/coffee/daytime refreshments, internet and AV equipment, and depending on the conference, flying speakers in. Then, at the end, you've got a couple of thousand dollars left over, and that goes on the bar tab. Think about how many dollars worth of alcohol you would drink during a two day conference, then drop the amount because there's a lot of buying in bulk and people who don't go to the parties or drink. It doesn't come anywhere near "most part of a $650 conf ticket".