Nah, I kinda agree. While there's reasons for theme (the ambient natural magic in the arctic is probably largely cold-focused, ferinstance -- it's the easiest kind of supernatural power to evolve over there), sheer Darwinian evolution is going to limit it's widespread use by every lil' creature, and, comparatively, encourage developing heat like the Remorhaz has.
It's a selective pressure. While it's easy to make frost stuff, and low-level critters would definately make use of it in light ways (if your prey is snowshoe hairs, adding a bit of cold damage is a benefit), the higher CR's would probably be dominated by heavy use of fire.
I mean, if there's no human-bane swords in existence, why would you be nervous carrying one being a human? Especially if you tended toward evil, it'd be a great boon! It's like the advice for different dragons in the Draconomicon -- they know their weakness, they're going to try to shore it up, and sabotage the weakness of others.
It does depend on what they're attacking. Normal critters, having frost is a benefit, because they have no special resistance. But anything that, say, has yetis making a selective pressure on them would definately be making use of fire in some way, or at least not making any use of cold in any way (because it's useless, after all). You get brutes, wolly creatures, huge sizes, and, yeah, fire.
Flavor-wise, think volcanoes, plate techtonics, and subterranean. If the main threat is from the weather, you shore up underground and avoid it, and get close to the underground heat and natural floes of lava and magma popular in any volcanically active region. Glaciers and volcanoes, caves, and mountains are natural allies, and often occur together. Or ice caps and water.
Think about the Norse creation myth for a techtonically active arctic, or about seafaring for an aquatic arctic, or wood and fey for an arctic plain. Arctic isn't a terrain, it's a weather condition. The terrain will be more pressured than others. A forest-arctic or sea-arctic might not develop fire powers, but a volcanic-arctic or mountainous-arctic may very well. And when that weather is dry and there are only vast rolling fields of snow and pack ice (a la Siberia), there is still the power of wind, the might of the sun, stars, or moon, the northern lights, and celestial energy.
So a few aides for the icy monster pallette:
* Cold Aquatic: Think swimming creatures. Cold damage would probably be quite rare but so would fire damage (nothing likes an unexpected swim!). You would probably find a lot of blubbery creatures, a lot of bulky creatures, a lot of creatures comfortable in phases of light and dark. The important selective factors here are rocky or ice capped land, and the worst predators are the sharks, beholders, etc. Speed, schooling, and the ability to kill and hold onto prey are the main strengths -- you get physical creatures, perhaps with mild stealth (white-on-black patterning), and a lot of congregation in groups.
* Cold Deserts: Here, you get some fire damage. The creatures here are few and far between, and white camulflage is nearly a nesseccitty, either that or the ability to burrow. The top-of-the-line predator here is an ooze, and the remorhaz more or less dominate the region. There's no problem burning anything -- just fields of snow. In fact, melting snow is probably one of the only ways non-cold-subtype creatures can get water.
* Cold Forests: A flowering of life! Bears, beetles, and predatory cats are the dominant forms of life, and finding fire damage would probably be rare, due to it destroying most of what protects the life. Though cold damage certainly provides an advantage over the many small fuzzies here! The only things resistant to your cold will be the fey and supernatural creatures of the region, which is a reason to carry torches, but not a reason to hone powerful fire powers.
* Cold Hills: Dragons, Beholders, and Giants make up the high end here, and a good many of them have protection against cold. Fire damage would not be honed to a great degree like it is in the Remorhaz, but it would certainly be used by a few high-end critters. Still, cold would see a lot of use. It gives you that extra edge for taking out the megafauna that live in the area.
* Cold Marshes: The mud of frozen fens is not a pleasant place. Hags, hydra, and dirty creatuers of many types live here, and cold would probably be a popular way to build items from the mud as well as fend off some of the marshy critters. The few creatures that can resist cold (like the cryohydras) can be driven off with poison, plants, or just avoiding it for long enough. Fire is probably very rare, but may be honed by high-end creatures like the Annis to better intimidate the local riffraff.
* Cold Mountains: The lair of the white dragons, giants, and trolls, this place will almost definately have fire honed to a good degree. Volcanic activity is likely, and those who forge weapons make good use of the heat deep within the earth to fend off the predators native to the region. The more intelligent, higher CR critters probably trade with those who have no vulnerability to fire to get them to forge fire-based equipment and weapons for them. Fire is not just useful for overcoming cold damage -- it's one of the few things that trolls cannot regenerate. Here, extremes meet regularly.
* Cold Plains: Like the hills, these areas contain a lot of megafauna, and they are often the most powerful individual creatures around. Frost worms tunnel through the area, but they use their cold to take down the wolly things. Most of the other cold things are weak, prolly preying on small mammals. Cold damage wouldn't be rare...fire damage might not be uncommon, though, either.