I suspect there is a market for this. My context is working with my biggest client who has used Mozenda and now Kapow to track pricing changes on 10K plus SKUs

I suspect there is a market for this. My context is working with my biggest client who has used Mozenda and now Kapow to track pricing changes on 10K plus SKUs across 5 to 7 major retail sites for the past 3 years for the retail segment that they operate within. Even given that they probably spend at least $1500 a month on independent price data services - some who have API agreements with one or more sites so they can access the data without crawling. Even with that larger scale volume of scraping there have still been sometimes that I wrote little scrapers for a site to track some changes. I don't write these little scripts very often. I will keep your service in mind for the next time this need comes up.