Andy has asked the question every business owner has had to ask at some point in time. It will mean the difference of life or death to the business. There is another thread on this site addressing the close of Niagra bikes. Tons of comments about how they will be missed as they always had the lowest price (such loyal customers!) Niagra must not have addressed the profit margin question or missed something really big if they did. Their pricing scheme probably cost the company its life.
When someone remarks "Business is about making money" it is most often misunderstood and vilified as an insensitive statement, but it is real and direct to the point. Profit margin is required to stay alive and the business is in the business of making money, regardless of the company's "mission" or "vision" statements of feel good BS.
When I was in the retail end of the biz full time the national average bottom line profit for bike shops was 4%. They ain't getting rich, folks, and I remember our competitors did what they could to undersell us. Well, we are still around, and only one of those competitors has stayed alive, and no longer undercuts on pricing. Funny how that works, huh?