In cas you are disabled the thought of a person voluntarily taking the role of a person with handicap probably is appalling for you.
We can understand this very well. We won't try to give reasons or explanations for our behavior here. We simply have the desire to do this and we know that it is better to follow this desire than to supress it.
Maybe now you say, ok, why don't they get a real handicap for themselves? Well, there are people who have exactly this desire (socalled wannabes), but we don't belong to this group.
We simply want to have the feeling to be "disabled" from time to time.
Some of us follow this desire only at home, some do it in public.
One important point only: We do not do that to make fun of disabled people. And we don't want to swipe any "privileges" which maybe are granted to disabled people.
And all pretenders we know take care to behave well in
public and we try not to do any damage to the image of disabled people.