Pinterest is mainly focused on pictures and its users like to scroll at leisure through long lists, collecting items that catch their eye. On the other hand, G+ is more focused on reading single articles: notice an interesting headline, read the first few lines, click to read more.
This distinction between grazing for images and hunting for text articles is why lack of horizontal alignment makes Pinterest more enjoyable and G+ harder to use.
Pinterest is mainly focused on pictures and its users like to scroll at leisure through long lists, collecting items that catch their eye. On the other hand, G+ is more focused on reading single articles: notice an interesting headline, read the first few lines, click to read more.
This distinction between grazing for images and hunting for text articles is why lack of horizontal alignment makes Pinterest more enjoyable and G+ harder to use.