Battleaxes and throwing axes aren't high crit. For Dwarves, TWF rangers, and heavy melee combatants in platemail, it's a good feat.
Dwarves have access to Dwarven Weapon Training (+2 dam with axes), so they're likely to use axes.
TWF rangers can use two one-handed weapons, and have some powers that can work with either melee or ranger, so they can get good mileage out of axes (particularly thrown axes for those melee/ranged powers).
Plate combatants (except for paladins, which start with it) require the Plate armor proficiency, which has a high Con pre-req. If you've invested in Con and (presumably) Str, there's not much left for the high Dex needed for blade feats. So might as well go axe, which likewise has feats with high Con pre-req (like the epic feat that gives axes a crit range of 19-20).