Well it was about time. I don't know why it took them so long? They have over 13 million users and are growing every week and one would expect that they would implement this long time ago. Reducing the fees will be welcomed by all of their users and will reduce the global impact of the rising fees.
It's the customers that want lower fees, Coinbase doesn't necessary care about it. They won't profit more then they already do when they implement SegWit, as they don't receive the fees. It will cost Coinbase money to develop SegWit implementation for their platform, I guess they rather take their time and save money. Their customers don't have to know that they can impact the transaction fees unless they tell them. Although I dislike this way of entrepreneurship, I kind of understand their decision, it's all about making profit.
