In a fast moving business world with multiple services, etc. how you market yourself, may or may not be different from others. You could for example offer free photography services (or any other kind of services in any other kind of line) in order to break into a network circle that you consider important, or in order to sell some other kind of service, or in order to support some other kind of service that is important to your business. Judging why a "competitor" (someone who is offering a similar service) is charging too low or too high is not very fruitful, although evaluating and understanding, why they charge and the way they charge (i.e. if they charge $10 for wedding dinners, where do they make money from) is mandatory and should be continuous.
Understanding the cost of depreciation of equipment is again mandatory, but remember, there is a whole bunch of assumptions there. For example, "assume 1,000 per wedding event then the camera life shutter will need replacement after xyz wedding dinners".. but in reality, someone might see things different "do xyz number of weddings for these friends, and it will link me with xyz number of people, assuming that I sell a service abc to these people which makes me $xyz,abc then the actual cost of a couple of D4 or D3X 's (insert your favourite brand and model) is not that much comparatively"...
One cannot assume "a 'photographer' is defined as someone who only shoots for direct income from the photos" all the time especially in today's competitive multidisciplinary interconnected world.