Which part doesn't make sense? I only carry runes of portals with me because I can't spare the extra bag space(yes, the one extra bag space) to carry a stack of runes of teleportation, if that's what you mean.
I would like it if they would have it so the tooltip for Teleport: spells read, in part, "Reagent: Rune of Teleportation or Rune of Portals." Better yet, Teleport: and Portal: could read "Reagent: Rune of Teleportation." And/or they could make a Glyph of Teleportation: "Your Teleport [and Portal] spells no longer require a reagent."
I'm still confused as to what you were referring when you said it didn't make sense.