Users are interested in apps that have no ads. Whether or not an app has ads is not part of the standard app info fields, so while publishers could lie in the t

Users are interested in apps that have no ads. Whether or not an app has ads is not part of the standard app info fields, so while publishers could lie in the title, where else can the users find out whether there are ads and why couldn't Google instead just ban apps that lie about having no ads instead of outright banning "no ads" in the title? I think Google makes no money from free ad-less apps, so it is plausible that allowing free ad-less apps to promote themselves as "no ads" (over apps with ads or paid apps) is not directly financially beneficial to Google and is perhaps even harmful. You can see the disincentives at work here.