I worked for a company that did this for awhile - they had custom written clients for all the major sites, just watching tables and recording the hand histories

I worked for a company that did this for awhile - they had custom written clients for all the major sites, just watching tables and recording the hand histories, which they provided as a subscription service. You could absolutely use the data to improve your margins. Think knowing how loose or tight your opponents were over thousands of hands. Then we got acquired by Zynga and that business got sold off.