Ever notice how your (place internet mail provider here) seems to know the content of your personal mail to target ads?
Fr' instance---your great aunt Petunia sends you a note about how great her trip to Mexico was, and suddenly, all your ads contain travel offers,
cuisine, language courses---etc ad infinatum.
I would really not be concerned about ATS cookies.
Cookies are a necessary part of the net, both for convienience, and revenue, and are reasonably safe if you use a modicum of savvy and discretion
about exactly which info you broadcast.
Just my dos centavos.