In CYVR for example, the runway whose texture hasnt been tampered with has a greyish look and in KPHX, the ground is kind of brownish, but the new texture just makes it stand out so much doesn't look like it belongs there. And its just one runway, at least in CYVR. The other runway looks perfectly normal.
As you can see from the default texture files I said to check in the default texture folder, there are many different kind of default texture files, each one for a different texture materials (as specified in the scenery AFCAD) so, if a 3rd party addon has replaced them with its own, they will "stand out" less or more, depending how much that 3rd party addon has make them different compared to the default.
Since not all runways (even in the same airport) are made of the same material, it's just normal that, if one of the textures assigned to a certain material hasn't changed much, while the one assigned to another material has, one will look "normal" and the other would stand-out more.
I'd expect that a 3rd party texture replacement product would not try to make them TOO different, because many scenery developers would probably RELY on those textures to have a certain appearance, and would probably design the surrounding textures based on that.
As I've said, this has affected several thousands of default FSX airports, not just CYVR ( or KPHX ), since the default FSX materials are not so many, and the most commonly used are just 3-4, used by thousands of default airports, and any 3rd party texture replacement product that would make them too different than default would look "different".