By constantly shoving products in potential consumers' faces it instills the thought of purchasing the product in the back of their minds. The more annoying the ad the better because if something is annoying it remains in people's minds longer. Product placement is more effective to dedicated watchers of shows or movies because a lot of times dedicated viewers wanna be like their favorite character, even if it means just having the same sweater or pair of shoes as them.
He expected it because Phaeacians were famous for their hospitality and willingness to help everyone. They would refuse help to no one so he expected them to help him.
