Yeah that's exactly what I was thinking. There's one edge case that I guess would still exist, where if you somehow used multiple different VLANs and then allowed the same IP addressing on each (like two diff vlans but they both had same IP). At that point you would need to instead preserve the VLAN information, or pass it further into the stack so that they could be categorized separately in the UI, but I don't forsee that situation being likely even with my weird edge case (all my boxes are on the same VLAN already).
If you're just looking to get some traffic with 802.1q tags, and your switch supports TRUNK or GENERAL mode, you might be able to add an additional VLAN to the switch port and it will keep that traffic tagged (since trunked VLAN traffic stays tagged, or any VLAN beyond the first one on a GENERAL port, which seems to combine TRUNK and ACCESS). You probably already know all this, but just in case it helps!