I have a lot to say here but I'll refrain from flooding the comment stream. Here are the highlights:

$20 for a ticket works only because of extensive sponsorships and reliance on a) free speakers and b) the support of the community including in most cases free venue space. While this may work for smaller communities and cities it is exceptionally difficult in larger cities like Vancouver, Canada. When we organized WordCamp:Developers in 2011 we reached out to every venue in town for even partial sponsorships. The response we got was often outright laughter. Vancouver is an event town and we were competing with every other major conference and event, all of which were paying full price. Needless to say an open source event with on a shoestring budget had no chance.

The only way events like WordCamp Vancouver can stay afloat is through massive funding through sponsors. This results in a perception problem from the viewpoint of the attendees. They only pay $20 and think the event is trivial while in reality it is a major undertaking with colossal costs. The low ticket price leads to significant attrition and sets a bar that is way too high for similar events offered at the same price.

We did a price comparison and found a total of zero other events of a similar events in this town at the same price. The next cheapest event was $50 and required a previous membership to an organization.

The $20 price tag makes WordCamp look cheap perpetuates the perception both inside the community and out that WordPress and WordPress work is not expensive. That is not a sustainable platform on which we can build a solid footing for the future. It was fine when WordCamps were small independently organized events more like extended Meetups, but now that WordCamps strive to become "real conferences" we need to raise the bar and the cost to make it all sustainable.