Of course, intention does matter. If a legitimate buyer wants to purchase Bitcoin legitimately, what he'll receive anyways, of course he is entitled to request this sort of information.
When you go to the groceries and pay with cash and get the change, do you ask the seller where they got the change from?
When you buy jewelery, do you also care about the origins of what you buy, or only about the materials that are used and the jewel itself? I guess the latter. In bitcoin, the "material" is protected by bitcoin itself, assuming there are enough confirmations in the network. So, why bother about the former?
If I get any amount of Bitcoin, I just do some coinjoins and then, everything works perfectly!