Do well known businesses still need to make effort in reaching out to their loyal customers?

Yes indeed, because:

1_ Loyal customers are your advocates – you don’t just sell them a product/service, you provide them with a great product and a great service to boot.  Such that they are pretty enthusiastic when it comes to talking about you to their colleagues, friends and anyone else that will listen!

2_ Repeat customers will easily go elsewhere if something goes a bit pear-shaped.  Loyal customers will sit it out – because they know that you’re there to sort it out for them, and it’s a genuine mistake (which you will have owned up to).

Yes.  Case in point: Coca-Cola

As the biggest multinational refreshment company, with arguably the biggest base of loyal customers, Coke is still the marketing leader, the latest example being the ribbon that could be made from the wrapper.  

Loyal customers appreciate a business that, regardless of being superior in most aspects, still has that willingness to make an effort.  The dual benefit being, loyal customers stay, and new customers are easy to capture.