MicrostockGroup

I can't imagine that the location is in any way relevant for anyone. You can search images by country, but I think the only information you get is how many photos originate from which country.
As for editing after submission, FT's constant reply to that is that they don't want to have to inspect more than once and that they want to avoid keyword-spamming. Which is ridiculous, if you look at the keyword-spamming going on and also the awful keywords their translation tool comes up with. They have been promising to improve that for years - nothing ever happens about it.

Location is very important to many buyers for certain images - problem is they usually need more than just a country, and having a search filled with images that aren't relevant because the category is compulsory for every image makes the feature next to useless. Nice idea at the start, but the implementation is a dogs breakfast.

You would think that, except a lot of photographers seem to think its smart to spam their keywords with multiple locations. The approach that Alamy takes is far better. Geotagging would be ideal.

As I said, FT's implementation isn't ideal by making it (a) a compulsory field and (b) not making it any more specific than just country. Obviously most people don't care where your generic group of students has been shot, but a designer looking for a travel image cares whether a beach is in Australia or NZ.

It is taken automatically from the IPTC field "country" (that I always fill in). Flickr and Clustershot add that info (city, location in city, province, country) to the tags, which is quite annoying for overwhite studio shots.