Data extraction has many benefits. It keeps you abreast with the latest prices that are being offered for the products of your domain and the list of the vendors that are offering the same. You can then study the same and set your prices accordingly, based on competition and brand proposition. It also helps by informing you when the product description changes so even if you miss out on something, you can always bring yourself up to speed. Extraction gives you valuable insights about your competition and grants you unprecedented market knowledge, which are the two most essential tools to help you become market leaders in your industry.
If you wish to extract data from website, you have two options. You can choose to do it in-house or you could hire a company to do the same for you, which includes outsourcing.