My Kirkland 2-wheel roll-aboard always has a book in the outside front pocket. Easy access for something that's already flat and relatively durable.

As others have said... wet/unsightly items from traveling with kids often get jammed in there, as well.

I often put the bottles of water from the hotel front desk in the front pocket for the quick walk to the room. My hands are usually full with other items.

I hope I never have to replace my Kirkland 2-wheel. It's my favorite bag ever... bang for your buck, better than Tumi and B&R.