Doing Anything That Makes Someone Seem As Less of a Person

The title really explains it all but I will go into detail on what I mean. There are a lot of possible examples that I can use honestly, as they can be easily interpreted as a way to portray someone as less than a human. One such thing would be looking at a person with a physical or mental disability. From what I have witnessed from one instance was when I was just writing something for a class in a cafe that I regularly go to, I noticed one day that their was a group of people with wheelchairs that were sitting by one of the tables by the entrance (it was one of the only tables that would allow all three of them to enjoy themselves and have enough room to move around). I glanced at them one time while they were there, since to me it didn't really seem out of the ordinary. Just three people sitting at a table, nothing strange about that. But what kept catching my attention was all of the people that were blantantly staring at them. It was bugging me that people were just staring for no particular reason at them besides that they were just in wheelchairs. From what I noticed, they didn't really look back but were just enjoying themselves. However I just think that they are just used to it from experiencing that from other locations and other times. While this doesn't seem that bad from the example that I have given, I just don't know how I would feel if I would have someone always constantly judging me on something that I am not able to prevent no matter where I go. After a while I feel like I would go completely nuts if I was in their shoes. At that point I feel like I would have been conditioned to be used to failure due to my disability. This isn't limited to just that though, but the idea also branches out to other forms that would also dehumanize someone. This also includes abuse, bullying, etc.