I have had certs refused on only one occasion: at the end of a flight, I offered two certs to an FA who had skillfully settled down a potentially-disruptive passenger. She thanked me profusely but very politely refused the certs. She told me that she had won the contest once, and had had to pay an inordinate amount of tax on the prize. She asked me to pass them along to someone else, as she stated that many of her co-workers didn't mind the tax implications.

As far as abbreviated Y drinks service on very short segments, one of the challenges would be setting up an entirely different set of rules and procedures; printing and distributing training manual inserts etc, and so on. The difference with WN is that their system is (essentially) their ONLY system - they do not have to worry about differentiation in crew training and on-board equipment.

Also, do the big LCD boards in the gate area specify that there is no beverage service in coach on these short flights, or not?