Trust me when I say that it is not our daily dream to use your public bathrooms that are only cleaned twice a week and usually have no toilet paper.........not my idea of a joy or pleasant experience.
We are speaking of those who have no other choice, other than voiding on your establishments floors, and being ridiculed for something that is not in their control.
We don't go out plotting to ruin a bathroom or bug a merchant to use theirs. You may find as well, that most who are inflicted with this disease or an ostomy are cleaner than your co workers. We have dignity, we have pride and most of all, we have a gracious nature toward those who allow us to live with that dignity , hence letting us use a toilet.....
Now, I ask you how you would respond if your loved one was inflicted with these diseases? What would you do if you were out and you or your loved one had a disease process that caused excruciating cramping and misery, but could be lessened or relieved for that moment by the use of a toilet? Would you be so quick to say "it is not a public restroom"? Would you in turn, go and walk that person or yourself across a lot or a block down the road knowing that each step could be the undoing of the control they have and and also increases the discomfort they / you are feeling?
I will restate your own words.....but to you this time "you're missing my point..."

We don't abuse the restrooms, as we know it is a privilege to use them and we don't enjoy the nastiness that we face when we do need to use them either. If you chose not to allow it, then pay the fine. I just hope you can sleep at night when you see the face on that person who, I am sure it took all their 'balls' to even ask, does not make it to the next place of business. That child, that teen, that mother/sister/brother/husband/father......... you may be amazed to learn how many people live normal lives with these issues, and you would not know it if they were in your store, until they asked you to use the restroom and informed you that they live with it....... We are not ogres, we are human beings.