No, that assumes people are rational actors and they are not; preying on human psychology doesn't alleviate you of guilt, the companies are the problem, not their victims for not leaving.
It's similar to a company selling defective products or contaminating a city's water supply. The market response is too late to deal with those types of problems, and undervalues individual lives.
Yup, and it's too reactionary to problems that can be easily avoided by regulation, food safety for example. If it were up to the market, people would be dropping like flies because safety doesn't tend to increase short term profits as well as corner cutting.
I don't think you need to even concede the idea that users are rational actors--there are plenty of reasons why a rational actor would prioritize another factor over security. For example, many people got Yahoo email addresses a long time ago, and built a personal contact list of people who only know their Yahoo email. A rational actor might value keeping in contact with those people over their privacy. That doesn't mean that it's okay to expose that person's data.
