Andy has an awesome post about the realities of small business IT. IT infrastructure is expensive, let alone trying to implement IT in a secure and scalable and proper way. Also let alone trying to afford staff or consultants to support that IT and security. This puts pressure on individuals, small companies, and even mid-sized business to spend that sort of money or accept risks. This puts more emphasis on lightweight and open source tools. Which puts more emphasis on IT staff with those kinds of skills. Which puts more weight on paying their salaries.
As Andy says, even implementing the most basic things like backups can be difficult and painful.
Ahh, the continuing conundrums of IT security.