Yes they do offer Crisps on Complimentary WF.
AFAIK the only thing that isn't available on a weekend is Fruit.
But quite often I am able to pick up: Nuts, Crisps, Fruitcake, Fruit (Weekday only), Danish Pastries, Olives (Yuck), Granola Square thingys and they did have those Frusli Bars but I haven't seen those in a while. My particular favourite was the Apple and Cranberry one (But would settle for Blueberry
I'm not sure if the fruit juices are available at weekends though. I have seen people ask for orange juice and get given the whole carton, served in a Tea/Coffee cup with lid, or be told they don't have it.
Now I no longer work in a 9 2 5 job, I travel mainly during the week to visit clients rather than weekends.