With online sales expected to top $100 billion this holiday season, e-commerce companies are increasingly relying on sophisticated software to convert visitors to their websites into customers, preferably repeat ones. Online shopping sites track all manner of info as visitors click around and fill — or don’t fill — their carts.

Among the information web merchants track are visitors’ product searches, the pictures they click on and what items they put into their cart regardless of whether they actually make a purchase. Users who browse a product on an e-commerce site will be served with targeted offers for that same product when they access other sites from Google (GOOG) and Facebook (FB) to their favorite news provider.

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Albert Gidari of Stanford Law School’s Center for Internet & Society argued in an email that the Cohen and Allen piracy lawsuits are “ill-conceived.” But he said the cases might trigger action by the Federal Trade Commission for unfair or deceptive trade practices, which plaintiffs’ attorneys “hate because there is no private cause of action for them to bring.” That’s because the lawyers don’t make any money from an FTC action.