sophisticated marketers have done hold-out tests with retargeting shown that it can drive incremental sales at a profitable roi. this includes big ecommerce brands.
granted not every viewthrough and clickhtrough conversion is driven by the advertising, but some definitely are and it is often profitable if a campaign is optimized and run well.
granted not every viewthrough and clickhtrough conversion is driven by the advertising, but some definitely are and it is often profitable if a campaign is optimized and run well.