Hubpages is definitely not a scam - they are one of the most trafficked websites in the world, and have been in business for many years.
Just like many other platforms on the internet, Hubpages gives its users the opportunity to leverage their platform and earn money based on the contributions that you add to their community.
If you post hubs or content onto the site that no one cares about, then you aren't going to make any money.
On the other hand, if you contribute high-quality content, then you can make some money here.
There may be better places to earn money on the internet, but Hubpages is definitely not a scam.