They're aware of the permeance of open-source in current tech scene and want to be a part of it than fight it. Not many startups (except for DreamSpark, BizSpar

They're aware of the permeance of open-source in current tech scene and want to be a part of it than fight it. Not many startups (except for DreamSpark, BizSpark, and Seattle/Redmond based ones) build on MS stack nowadays. MS audits are dreaded (thanks to Oracle for showing the way) and a diversion for a growing startup. It's better to steer clear of MS & other proprietary tech whilst building a startup. They're embracing startups since they need them and are changing their business models to cater better to smaller startups than the behemoth enterprises with Office 365, Azure, etc.