I've been involved in the open source community in one way or another to varying degrees for basically my entire career, and I can say with a high degree of certainty that if it weren't for open source, my career would've probably gone a completely different path.
"Open" has grown to mean more than just access to the code, and now often implies the sense of community that comes with using open source software. Need some software that will cook your breakfast for you? If such a beast doesn't already exist, you can safely assume that someone out there has written most if not all of the supporting sub-functionatlity, and then its just up to you to cobble it together. Support? Sure, 24x7x365x$forseeablefuture by people around the globe who aren't doing this for the money, but rather because they are passionate and knowledgeable about the project. AI::MakeMyBreakfast doesn't do exactly what you need? No problem -- add the functionality, make improvements, and the project will happilly accept your work.
Like every story, there is a dark side to open source. The dark side that I speak of are vendors that speak badly of open source. Their reasoning is never clear, and as a wise man once said -- "The proof is in the pudding". If your product is truly better than a competitor's, even if that competitor is an open source offering, prove it using solid, no-bullshit technical facts and a real-world bakeoff. The real reason they bash open source, in my opinion? Fear.