[thih9]

The article mentions that too, although as a secondary explanation for some reason.

> it's said that the inclined casts of mortar also had the task to maintain a certain public decorum and therefore prevent Venetians from urinating in the corners of the calli.

[mhitza]

I rather buy the idea that the secondary explanation is actually the primary reason. In the first picture you can clearly see such a structure in a corner that doesn't connect to any kind of street/alley. Thus, I personally, don't buy the primary reason. Of course, unless that specific spot was made much later in time.