Patenting ideas that are really not yours?

I did some more research on patent myths and read this article from Entrepreneur.com: Top 10 Patent Myths

I feel compelled to post the intro of the article:

Given that most businesses aren't built on truly original ideas, patents can seem like more trouble than they're worth. However, integrating patents into your business plan, regardless of whether you're an inventor, is one of the most overlooked elements of a successful business.

[Read it it's worth your time! Esp if you want to start something of your own.]

Given the idea of patenting still remains relatively new to most smaller-scale businesses, this strategy could potentially lead to the success of many. However, I also question that if this complies with the original purpose of a "patent". Isn't it really to protect innovation and new technology? Apparently there are loopholes out there that businesses and people can take advantage of.