That is true in sandbox.
In competitive places, like arenas are, you won't be running Deathfrost, you won't use your CPs to S'n'D - Vanish - CS - KS uninterrupted 10 seconds of beating yolo me smash you die thing....
No way, unless you're playing against very little experienced player, or you're one.
In such case, these people should learn how to avoid such a scenario in the first place. Whey they do, you bet they'll realize that Glaives were not their problem at all.
/Edit:
The point was that the Glaives obtainable in the Marketplace are not a problem for both PvE and PvP competitive players as there are more than a good alternatives to it.