You're getting way too strung up on the specific example of cleaning toilets. You know what job vastly more people will want to do? Installing and maintaining a self-cleaning toilet. Bang, massive benefit to the local community. Focus on profitability creates a blind spot.
I don't see why you think inflation would suddenly happen. You haven't justified that claim.
Also, anality drives me to at least mention the most straight forward way inflation will increase. You'd dramatically increase monetary velocity, which is what drives inflation, all other things being equal. Of course all other things would not be equal in this scenario - they'd also be changing in ways likely to drive inflation so you'd get a compounding effect.
Have you been in a public bathroom, in the US, in basically any urban area? Self cleaning doesn't cut it. People cause damage to bathrooms for no apparent reason, piss everywhere within a 10' radius, and on occasion feces isn't far behind. Oddly enough even women's bathrooms, at least on occasion, can be just as bad if not worse - as you can add blood to the entire disgusting mix, people flushing pads, and so on. Cleaning public bathrooms is an unimaginably awful job that nobody, in a million years, would do if they had any other remotely reasonable way to get money, let alone getting handed it for free.
Inflation happens because increasing labor costs will inevitably get handed right back onto the customer, especially on the scale we're talking about. And the customer isn't just the final customer, but every business operation from the raw goods all the way down to the final product, so it'd lead to rather dramatic inflation.