For the most part, every social media channel appeals to certain demographics. While users may run the gamut of ages and gender, the heavy users are the true indicator if a social media channel is right for your brand.
Your goal should be to find the sites that offer the largest concentration of individuals who match your target market and also appropriate posted content. It is more beneficial for your brand to commit effort and resources to sites that will provide the best return. Spreading yourself too thin by trying to utilize every social media platform may result in lackluster results from all of them.