Laundromat Simulator Demo First Look - Laundry From a Different Perspective! Episode 1 

You don`t need the change machine if you have card readers in your washers and dryers

You don't have to keep on taking out the money from the washers and dryers. Let them sit for a while. You'll see a green mark start filling the money sign.

The coin machine is to give your customers change to use your washer and dryer