There is another significant layer, which complicates the ethics of data and power. The data all of these firms collect is proprietary and closed. Analysis of human behavior from the greatest trove of data ever collected is limited to questions of how best to harvest clicks and turn a profit. Not that there is no merit to this, but only these private companies and the select few researchers they bless can study these phenomena at scale. Thus, industry outpaces academia, and the people building and implementing persuasive technologies know much more than the critics . The result is a fundamental information asymmetry. The data collectors have more information than those they are they are collecting the data from; the persuaders more power than the persuaded.
Judging whether this is good or bad depends on your framework for evaluating corporate behavior and the extent to which you trust the market as a force to prevent abuse. To be sure, there is a desire for the services that these companies offer and they are meeting a legitimate market demand. However, in a sector filled with large oligopolistic firms bolstered by network effects and opaque terms of service agreements laden with fine-print, there are legitimate reasons to question the efficacy of the market as a regulator of these issues.