They don't any more. At most startup companies they can't afford a typical bureaucratic IT department. Many use cloud hosting to avoid up-front cap-ex in terms of data centers and the people that work in them. Developers are typically managing their own servers, their own NOSQL cluster, they bring their own iPhones, gPhones, xPads, etc. People are becoming increasingly more comfortable with technology and old-school IT departments are no longer enablers, but barriers as their mindsets and their technology pale in comparison to the consumer sector.