If you buy a new Harley (or a new anything for that matter), you can expect depreciation. I've found that a Harley will hold its value much better, if you buy the right Harley. For example: any big twin Harley will never drop below a value of 5-6 grand, and if you hold onto them long enough they go up in value. I actually made money on my first Harley
Springers are a good example of a Harley that will hold their value. You will never find a Springer as cheap as an equivalent bike with a glide front end. They are somewhat rare, depending on the model, ad so demand a higher price. If you buy the right year, the value will level off and you will never be at a loss if you need to sell.
However, I hope never to have to do that. One of the main reasons I like Harleys is they are a bike for life. If you look after them they will last forever. Take a Springer front end as an example: it is old technology, but it works and it lasts. The main reason they stopped making springers was the front end was too labour intensive and expensive to make. They also can't have ABS brakes with a springer, which means they can no longer produce them due to certain US legislation, which makes them even more desirable
With regards to merchandise: not everyone can have a Harley, but everyone can have a t-shirt. It's no wonder they make more money with them than the bikes, they've marketed themselves as an image as well as just a brand, and some people will buy into that
Don't get me wrong, I don't care what you ride, as long as you do it safely and have fun on two wheels that's all that matters.
PS: only one model of the new touring bikes is water-cooled, and it is 'dual cooled', so only the heads around the exhaust have water-cooling. It isn't something that appeals to me, and as you say more can go wrong, but I think it was aimed primarily at people in hotter climates that could do with the extra cooling in traffic etc.
Another 'joke' to rile everyone a bit: 'How can you tell when someone doesn't ride a harley? They'll spend hours trying to justify why a jap copy was the better option'