I think (repeat think) part of the reason for 'special treatment' is in case of emergency.

AA has a manifest code for it to alert the FAs etc... and they discuss who will be responsible for the pax with various impairments during the FA briefing before the pax board.

BLND - Passenger is visually impaired
....
DEAF - Passenger is hearing impaired
.. there are many more.

Some hearing impaired pax can read lips at a close range while some cannot and rely in signing. I worked with a hearing impaired person who could hear low sounds and when we needed his attention would bang on a flour bin (it was a bakery) if his back was to us and he needed to be aware of something.

The main reason is YOUR saftey. In the event of an emergency you would not be able to hear the 'instructions' of where to go to what slide and how to exit the plane.

Accept the assistance and pray you never get into an emergency situation. The non-emergency part of traveling (delays, gate assignments etc) can be very daunting even for us hearing pax ... with poor PA annoucements and captains whose accept is to southern to understand!

I have noticed numerous pax with companions who sign. I can say I have not noticed a hearing impaired pax alone because, as you say, you act just like everyone else!

Safe travels!