Try playing a crowd-controlling fighter trying to herd enemies attempting to spread to the four winds. They're not exactly standing around idle. Movement is important to everyone in this game, but some archetypes can absorb stray hits better than others.
Besides, if the change I'm asking for were to happen, it would have this effect:
- Rogues would have to spend 1 fewer ability point to be able to get the Talent.
- Rangers would have to spend 1 more ability point to be able to get the Talent.
Er.. what? How exactly is that a convincing sell?
Look, since you seem to think having to "spend 1 more ability point" isn't a big deal, then let's just keep things as they are and let the Rogues continue to spend 1 more ability point (rather than trying to pass that burden on to the Rangers).
Rangers can usually afford the extra point cost a bit more than a Rogue can.
I sense a little bias in that claim. I can't think of a single class that couldn't use some extra points.