A janitor or cleaning service comes in and cleans once or twice a day...but this machine would be for the customers to use. How many times have you gone into a public restroom and there is urine or feces on the toilet? This machine would be for our use to be able to disinfect the toilet immediately and be able to use it without fear of what could possibly be in the urine or feces. I have had to wipe off the urine or feces with toilet paper and then put toilet paper on the seats and sit down. Wiping off the urine or feces with toilet paper doesn't kill any germs and it certainly doesn't remove all of it. I feel that this machine would revolutionize the way public restrooms are used. They already put condom machines and tampon machines in public restrooms and charge for those...why not for a machine that would clean off the urine and feces before they sit down on the toilet? A janitor or cleaning service is certainly not going to go in and clean the toilet after each person uses it. This would be for those inbetween times when the toilets become caked in urine or feces...or even blood for that matter. The company doesn't have to charge for usage of this machine...I was only thinking that it might help the idea take off for the companies if they were able to compensate for the cost of the machines and for the refills they would have to buy.
I have added a rough sketch of the disinfecting machine. I hope this will help you to see my vision. You mentioned different smells and that sounds fantastic. It would be great to add different smells such as, lemon, lavender, fresh linen, and even fun scents for the holiday seasons. The possibilities are endless.
Even for non germaphobes this idea would be nice, but imagine how many more people, who are afraid of germs, will be more willing to use a public toilet when they're out and about.