Sometime back I remember reading a paper where it was hypothesised that using hands is less hygienic than using toilet paper.
And to demonstrate this they used human stature (height) as a way to workout the effect of this practise on health and well being, and the results were constinent with the hypothesis.
Conclusion: People are taller in the countries where toilet paper is used.
Unfortunately, few minutes of googling didn't turn up any links now.
The problem with using hands is that the people often shortcut and do not wash hands properly now if you don't use hands, then this entire problem disappears.
What do you value more, then money spent on toilet paper or the time spent washing your hands properly?
The law of life is that people will often take shortcuts where it is possible to take one and along the way suffer consequences which weren't in their mind at that point because all they wanted to achieve then is to get through this fast enough to do something else later.
To get best of both, there can be a service where someone else washes you but then you lose privacy and you need to allow others to touch you but then it's also possible if that person's health suffers then you might also suffer on subsequent contact.