Mine seems to be the same, if not better, than my old standard 3DS and my current Japanese 3DS.
If it bugs you too much, just take it back to the shop and explain what the problem is, I'm sure they'll understand and give you a replacement or a refund
I think I'm treating it too much like a phone touchscreen because I'm making the tiniest bit of contact with the screen. Though I swear my old 3DS could handle that. Meh, I'll get used to it
Why not try re-calibrating it?
My screens are incredibly sensitive. I have to stop being so.. Well heavy handed with it a bit since my old DS' (before 3DS) had to have the screen handled a bit harder to get it working.