Is this sarcasm? Is this not one of the main strategies in lead generation? Linking email addresses to facebook accounts to groups they're involved in and deve

Is this sarcasm? Is this not one of the main strategies in lead generation? Linking email addresses to facebook accounts to groups they're involved in and developing target markets for certain users and selling those lists (ex. gamers) to less-than-reputable and maybe even reputable marketing companies seems like it could be profitable... Maybe I'm naive?