About your question. But you already have separate templates?
Each character made come with two weapon templates: One for PvE and one for WvW, with PvP being hidden in both.
And each character comes with 3 build tabs:
One for each game mode.
I'm not saying I disagree, I just want to make sure your question is answered. I also think templates being sold to us is a convenience cash grab for sure, especially since you had unlimited build space (I think locally) on GW1.
I actually haven't bought any and if I want more templates, instead of buying one of each, it costs the same gems to buy a character slot, which comes with 2 equipment and 3 build templates instead of just the 1.