When I shop online for, say, travel...
I'd like the site to auto-populate the origin city based on my IP address. If I close the window while I comparison shop and come back to the site, I'd like it to remember and fill in my origin, destination and dates, based on the last search I did.
If I don't convert in that session, I'd expect the site to follow me around and give me specific details on the search I ran, which may convince me to convert - a good price point, a discount code, a special offer.
I'd expect the site to figure out if I'm likely to shop online, and if so, if I'm a high value prospect, and decide how often they want to follow me around with the repeat messages, when they should show me those messages, and what kind of discount they should bother offering me. I want them to have the sense not to bother wasting their ad dollars on me if my past purchase behavior & profile show I'm just not worth it, or that they'll spend more than they'll earn from me.
People, even traditional marketers, are often surprised when I state these expectations, and it invariably sparks a debate on privacy. See, I don't believe any of that is an invasion of my privacy, any more than when a restaurant employee remembers my order because I've been there before, or tries to convince me to try the house special, or add extras to my order, or asks for my contact details so they can offer me discounts on my birthday and anniversary.
As long as the restaurateur/advertiser is anticipating customer needs & staying one step ahead, everyone's happy.There's just no downside to smart selling, it's the good old-fashioned meeting of common sense and customer service.
As a consumer, I'm more insulted by businesses, both online & offline, which don't try hard enough (or smart enough - nothing like getting emails about a trip you researched for dates one week out, 8 months ago), than by those that seem to know all about me.