Queue (Spreads) & (String) differences that shoudn't be

I’ve just noticed, that Queue (Spreads) outputs (nil) when no Value has been inserted and only after klicking Insert there is an output, while Queue (String)'s Output Spreadcount is always = Spreadcount.
Why is that? I like both situations, but only, if the Queue Nodes can be switched between the fixed output spreadcount and the incrementing Spreadcount.