nuget.exe delete warns about API Key for local sources, even though it makes no sense

[spadapet]

Using nuget.exe 3.4.3.854

REPRO

• Pretend that you have a local file source that contains newtonsoft.json.8.0.3
• nuget.exe delete newtonsoft.json 8.0.3 -Source local

RESULT
WARNING: No API Key was provided and no API Key could be found for 'f:\local'. To save an API Key for a source use the 'setApiKey' command.

EXPECT
Don't show that warning since I will never need an API Key for my local source

[spadapet]

NOTE: Nothing is broken, this is just confusing