Is there an element of hakaras hatov or some other obligation upon a listener/reader to pay attention to ads in return for whatever benefit the person is enjoying?
Obligation? No.
Anyone who puts up a website does so with the full knowledge that not everyone will read the ads. Anyone who advertises knows that not everyone will read the ads.
Do you feel an obligation to read every advertising billboard along the highway?
Do you want to do it as a measure of hakaras hatov for those who put up the site? Then go ahead, no one’s stopping you.
The Wolf