How would you feel if the information that you shared with a company you trust was then sold to another company?

When a marketer truly understands a customer it is much easier to meet his/her needs. So on one side marketers have the desire to collect every piece of information about a prospective customer, while also not being too familiar. How would you feel if the information that you shared with a company you trust was then sold to another company? What activities do you do to protect your privacy online? What about your privacy through mobile? What do you do to protect your privacy in a retail environment (store, restaurant, etc.)? What information are you willing to share in these environments?