Everyone has to go. Pregnant women and all of us as we get older, a bit more often. Yet there has actually been a decline in truly "public" toilets in many cities. http://www.ledevoir.com/politique/montreal/412104/le-retour-de-la-toilet... http://en.wikipedia.org/wiki/Public_toilet
http://www.francoischarron.com/iphone-trouve-la-toilette-la-plus-proche-... Ça presse: guide to toilets compiled with the help of the Inflammatory Intestinal Disease Foundation: http://www.ca-presse.ca/ (site seems down).
Cross-Canada public (and public-accessible) toilet map: http://www.powderroom.ca/fr/cross-canada-bathroom-map This has a very limited number of entries.
In a broader sense, public toilets can refer to toilets located in libraries, other public buildings, businesses (including restaurants and cafés), shopping centres and the dubious ones at filling stations, provided one does not have to consume to use them (very frustrating when one has to pee and is obliged to ... order a coffee).
Everyday sexism in public toilet access: http://time.com/3653871/womens-bathroom-lines-sexist-potty-parity/ In Victorian London, women's public toilets were actually deliberately discouraged to keep women "off the streets". And there is the related issue of access for transgender people.
And, of course, the issue of universal access, for people with disabilities, parents with babies to change etc.
I was happy to see clean public toilets for the customers at Supermarché PA (avenue du Parc, Mile-End Mtl) and Fruiterie Milano (actually a supermarket now) boulevard St-Laurent, Petite-Italie, Montréal.