Connectivity for Spies

[kinghchan]

I have a question around the design decision behind group tags and spies.

In UDP, say I create a publication over a channel that is tagged like this: fc=tagged,g:101
The channel also has ssc=true.

If I create a UDP subscription without a gtag, as expected, the publication won't become connected.
If I create a UDP subscription with gtag=101, then also as expected, the publication will become connected.

However, if I create a spy subscription without a gtag, then the publication will still become connected, because ssc=true (also as expected).

My question is regarding this design decision: why are group tags not applied to spies? It would be immensely helpful if I am able to mark certain spy subscriptions as those that will not affect the connectivity of the publication, in the same way that UDP subscriptions do when they omit the gtag.

Thank you!