This frustrated me to no end since the beginning of 2.0, but I just discovered it. Dunno if anyone else was already aware... but I think it's worth a topic
When trading currency for X item, usually you need to pick it out of the inventory... but if you right click or press SQUARE on your controller the item being asked for, you can pluck it right out of your inventory without looking for it (or going to if you knew where it was).
Why this wasn't made immediately obvious I don't know, but I want 2 weeks of sub fees back from Yoshi
Actually, why the interface doesn't just take your items like a shop takes gil I don't know... why is some things so backwards lol