How about a gentle, relatively quiet but discouraging audio tone that activates when the swinging door opens? Something like "uh uh", "uh oh", or "wah wah ~waa

How about a gentle, relatively quiet but discouraging audio tone that activates when the swinging door opens? Something like "uh uh", "uh oh", or "wah wah ~waaaah~" that is audible within, say, a x=20 foot radius. Maybe triggered only on subsequent usage within a y=10 minute window. One might argue it discriminates against the handicapped, or causes them unnecessary discomfort. I would draw an analogy to seatbelt reminder tones in cars. They cause unnecessary discomfort to everybody but are so mild as to be worth it, overall.