We have one at the cabin. They're silly and fun and the blunted ones sting just enough...
I can think of a long list of hunting tools I'd use before blowguns. If it's that bad, I'd probably use traps (I can trap in multiple locations) but assuming I had to hunt without guns, bows, etc. I think one of my throwing axes would be higher on the list. Even societies that use blowguns treat them as a niche skill.
It's a cool toy but I wouldn't take it seriously. I'm with Fyrediver, it's a cocktail game for me. I'd love to be proven wrong, though.