I’ve talked with a fellow who has recently built a house and he said there is no vent pipes through his roof–the plumber just used one-way check valves for venting the drain lines. I’m getting ready to shingle my roof, dry-in stage, and haven’t installed any vent lines yet.
A lot of folks call themselves “plumbers” but it doesn’t necessarily make it so.
This crap, garbage junk your describing sounds like an air admittance valve that some low life code officials approved.
It must be nice to be able to buy a code official and or a politician or judge to approve a piece of plastic and rubber crap to protect folks from methane, hydrogen sulfide and other cancer causing gases from entering the home.
Mechanical devices fail and these things are installed by the get in get out and thankfully I don’t leave there mentality stumble bums of society who just do not know any better.. Good luck