Right - if you cared enough about looking at anonymous salary information across different countries, you could just use Glassdoor.com.

The point of this app is that you share a link with your peers, whether they're based in your office or in an office in a different country. This is a bit different from completely anonymised data from statistically similar market segments (and possibly more useful, since people at the same company are likely to have similar perks and benefits etc.)