Sorry for reviving an old post but I just ran into this same issue on my newly purchased SG-4860 running 2.3.4-RELEASE-p1
This doesn't seem very intuitive & seems like it could potentially cause some unexpected & problematic behavior if someone deletes a LAGG & then tries to use the ports individually without being aware of this "functionality".
The reason being, when you assign interfaces to a LAGG, they all are given the same MAC. The potential problem (and definitely unexpected behavior) is that after removing the interfaces from the LAGG they all retain the same shared MAC!
In the attached screenshot you'll notice that igb4 & igb5 have the same MAC. That's because they were assigned to the same LAGG at one point & then removed. This was definitely not expected behavior & took me a while to figure out why it had happened since I had never manually set a spoofed MAC on the interfaces directly.
Is this behavior really functioning as intended?
Interfaces.jpg
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