Most travel experts think Ryanair's announcement that it is considering charging for bathroom access on the plane was purely a PR ploy. But I think it was more in the nature of a trial balloon.
Yes, Ryanair is justly regarded as a publicity hound; but it seems to me the carrier is merely carrying the ancillary revenue business model to its logical conclusion. Unfortunately, in this case their logic escapes me.
As many bloggers  have pointed out, what happens when a passenger hasn't the cash but needs to use the facilities? What then? One canny blogger at Freakonomics  also makes the point that airlines which charge for restroom use could be shooting themselves in the can, so to speak. That's because the bathroom fee is clearly a disincentive for passengers to drink or eat on the plane. So while an airline might make a few extra bucks in pay toilet change, it will be undercutting its own in-flight sales of drinks and food.
Beyond that, where do you draw the line on services that ought to be considered genuinely à la carte and services that are basic and integral to a flight? For example, I don't think the airlines ought to start charging for the use of those "emergency relief bags" that are stocked behind every seat. Can you imagine ringing an attendant and doing a cash transaction between the time you feel queasy and the time the aforesaid item finally makes its way to your seat? It's ludicrous.
Equally ludicrous is the idea that airlines ought to charge for such basics as water, air, your seat, and the toilet seat. While I think this all started out as a viral marketing gimmick to stir grumpy bloggers into creating a firestorm of publicity for Ryanair, it seems to have assumed a life of its own. I think this phenomenon is part and parcel of the cultural acclimatization that is occurring in the air. Passengers are still accommodating themselves to the idea of paying for what was formerly free. So theories abound on what's next. In fact, some bloggers  were speculating about a bathroom fee well before Ryanair broached the idea.
One thing I will say about fees for basic services is that as more of these trial balloons are floated, customers need to voice their opinion. If you think something is over the line, you need to say so. The airlines are in an operating environment in which they have to listen to their customers. Their customers are the ones who told them they wanted lower base airfare fees and greater choice. If the airlines fly off course in expanding choice with inappropriate service fees, it's our job to tell them what we will accept and what we will not. You may think bathroom access fees are a joke, but if you don't tell your airline what you think, some day you may find yourself hoarding those Susan B. Anthony dollars for use on your next fling into the wild blue yonder.
Road Warrior • Miami • www.us.amadeus.com