There are something like 33 countries who do have birthright citizenship but most of them aren't as developed or as pasty white as Canada or the US so they don't count.....to certain posters anyway.
The difference is that people are not going to fly into Venezuala to have a baby so their offspring will have the glorious opportunity of future membership in a Socialist paradise. There isn't the attraction as there is for third worlders with the chance for citizenship in a wealthy western country.