I find this debate interesting. However, it's ultimately is up to the individual designer on work they choose. If you're an art director at an agency, or don't need to be on these crowdsourced sites, then don't.

Sales folks spend time on presentations and prep for business they never close, and some of the top tech companies the Valley require engineers and designers to complete projects as part of the recruiting process.

As founder of a crowdsourced design site (fantastic.me), we see this issue often. Here is a blog post I wrote on our position, and how we think there is business model where everyone wins.

http://blog.fantastic.me/2012/07/is-crowdsourcing-design-rac...