Many consumers have reservations about online behavioral targeting. By tracking users' online activities, advertisers are able to understand consumers quite well. Advertisers often use technology, such as web bugs and respawning cookies, to maximizing their abilities to track consumers.[60]:60[95] According to a 2011 survey conducted by Harris Interactive, over half of Internet users had a negative impression of online behavioral advertising, and forty percent feared that their personally-identifiable information had been shared with advertisers without their consent.[96][97] Consumers can be especially troubled by advertisers targeting them based on sensitive information, such as financial or health status.[95] Furthermore, some advertisers attach the MAC address of users' devices to their 'demographic profiles' so they can be retargeted (regardless of the accuracy of the profile) even if the user clears their cookies and browsing history.[citation needed]
Push marketing is a proactive technique that enables e-marketers to "push" their product/service information to Web visitors or shoppers without their requesting it. Banner advertising, pop-up advertising, e-mail promotion, and spamming belong to push marketing. For instance, e-marketers can rent designated space from Internet service providers such as America Online or MSN for their banner or pop-up ads. Using animated graphics, appealing messages, and links, e-marketers try to lure visitors to their sites to buy their products or services. Many Internet users, however, find such ads annoying and employ software that blocks pop-ups and banner ads. <
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