You raise an interesting point in the first sentence. It might be that age sniffing could actually violate the US constitution.

As for lobbyists: I think we can probably determine the key lobbyists, e. g. if we map the data and names. And ideally also the money given to them. Ultimately they are faceless though, because corruption is easily exchangeable. The issue here is systemic though. The US "democracy" no longer exists due to that corruption. It is not rule by the people but rule by bribery.