Re: This is a very good example
> If I am caught short in cold wind, ... plants or a drain, which nobody can see. ... can't see the point of your post.
As you correctly point out, public urination is treated, legally or socially, as an offense. You argue that these rules should be relaxed, that it is socially acceptable to urinate in a 'discrete' place.
The problem is, you and I may differ on what we consider to be 'discrete' - hence the need for legislation.
There is also the issue of whether 'discreet' peeing is "cumulatively tolerable".
TV coverage of footballers spitting on the pitch made spitting more socially acceptable. While one sportsman clearing his throat may not present a major health risk, this has led to a rise in people spitting in public, and a corresponding increase in public health issues.