There are ISPs that have tools to inject arbitrary code into HTTP webpages. For example, My ISP injects notification banners into my web browser sometimes. Eve

There are ISPs that have tools to inject arbitrary code into HTTP webpages. For example, My ISP injects notification banners into my web browser sometimes. Even if the ISP means well at the beginning, the tool can be abused (ISPs injecting tracking, or reading the tracking information so they can sell it). Attackers at coffee shops and conferences can do much worse.