Google Scholar is just an indexing machine providing links to journals, so in most cases you still need access to the journals to access the papers. That being said I do use Google Scholar a lot - Its search function is better than that of Pubmed, but Google does have a bit of expert experience in that area, or so I've heard.
And regarding the link you posted - Sham journals scamming authors is definitely a problem. They are pretty annoying also. I get emails from them once in a while.