Honestly, this seems pretty typical to me. If you want the idea implemented, you might have to accept the situation. Alternatively, you could make your proposals directly to the manager, or just sit on them.
Obligatory quote: "Don't worry about someone stealing your ideas. If your ideas are any good, you'll have to shove them down people's throats."
Obligatory quote: "Don't worry about someone stealing your ideas. If your ideas are any good, you'll have to shove them down people's throats."