I do agree Agile is not right for every situation.
However having run small technology/development companies, I can say that being agile with a focus on doing just enough in the moment from a value perspective is the way to maximize your investment in people and technology.
Where small organizations get often get screwed finanically is when they contract outside firms who work in waterfall. These projects almost always have more work committed than needed and have a high risk of cost overruns for any change that occurs during the life of the project. Change requests literally can be counted as their own profit center.....