It is true that if they have a tiny sample in a large country, their result could be very wrong for that country, and leaving it small and not size-corrected would at least leave that error small.
But, even 200 sites per country is enough for a proper random sample (that's about the same size as in election surveys). Even more so when you consider that a site is not a single observation, but reports data about all the users visiting it.
>But, even 200 sites per country is enough for a proper random sample
Yes, but my concern is that they may only have a handful of sites (or none at all) for a long tail of smaller countries.
>Even more so when you consider that a site is not a single observation, but reports data about all the users visiting it.
True, so it depends on whether or not users of popular international sites from a particular country are representative of all users from that country.
But, even 200 sites per country is enough for a proper random sample (that's about the same size as in election surveys). Even more so when you consider that a site is not a single observation, but reports data about all the users visiting it.