I'm older, not wealthy, and live alone in the country.
The bird dogs I have are my family, in a sense. I understand the different points of view of ownership, but once I've accepted a dog as a hunting companion, I accept his level of ability and work to improve and hunt within it.
The past few years I've had my first flushing dog--vastly different from the two versatile pointers (GWPs) I have previously been blessed with.
For good or ill, Mick has compelled me to learn a different style of hunting, and accept (and attempt to enhance) his level of ability. In turn, he has tapped his instinctive capacity for the joy of the hunt, and curtailed his enthusiasm within the bounds of learning and obeying my commands. I still marvel when he stops in his tracks at my "hup" command while pursing a running rooster.
OP's question about "value" of a dog...well, kind of stumps me, although I assume it was a thought-provoking inquiry.
To me, the dog IS the hunt, just as the shotgun is, and the many roosters and few ducks are. From my point of view, the question may well have been "what value is breathing to the hunt?"
For me, and perhaps me alone, there is no hunt without my companion.
Be safe, have fun.