WOW I am the odd one out here!
There is no way I would fill my babies cup with water from a public tap.
I would spend the $2 and buy a bottle of water... (you could get three bottles for the price of a happy meal

)
I actually saw a women do this the other day and had this conversation with both my husband and mum and they both agreed with me.
Personally I wouldn't use a tap that people had touched after using the toilet.

Call me a nutcase, odd, strange, moron, blah blah, blah...
In fact at home I boil our drinking water or purchase bottled water. For me the fact that our local dam is so low and the extreme age of the pipes in our area I think it's best to be safe then sorry.
We are all different....