Advertisements can be useful in having business companies earn money that way but should there be wrong advertisements that infect the visitors' devices, it can be a serious trouble after tons of users are complaining about that situation. A recent situation is that Google has owned the DoubleClick technology that allows advertisers to manage advertisements on behalf in the respective websites. Perhaps, there should be trusted ones that don't allow illegal activities to take place in victims' devices.
One example is that cyber-criminals can hijack various websites into replacing the professional ads with undesired ads that do harmful thing to the website visitors' devices but another recent situation will take you back to the days of the Lenovo Superfish scandal in which Google has taken actions in. Another problem is that even some evil ISPs are doing the same thing as stated in the above example but this is what the companies are to worry about undesired ads on their sites injected by the ISPs themselves. For normal users, it's easy to get around this situation with the Ad-blocking extensions in the web browsers.
Unfortunately, Google should have taken actions against ad injectors earlier as the ISPs in the US might have gone way too far. The privacy is violated there over those bad ads, other malwares are injected on ISP broadband routers and certain services belonging to them doing the same violation thing as well.
