You'll see from my post count, that I rarely visit these boards, but as one of the puzzle cache setters in Surrey, I thought it worth posting my thoughts. If you lack the time or inclination to read it all skip to the last paragraph, where there's a summary.
I got into caching via a colleague at work around a year ago, and the first cache I tried was Brambler's Pitch One. I failed to find, but was hooked. I then set off to do some local non-puzzle caches, but kept heading back into the hills to try and complete the Pitch series (which to date is still my favourite). I enjoy caching mostly as something to do when I'm out walking the dogs on my own, and because it takes me to places that I wouldn't normally go to walk.
I have eight caches set, and all are puzzles. Why? Well there are many reasons for it, but they start with the fact that I enjoy setting them. I enjoy the research, and that eureka moment when you can fit an idea into a cache. I spend more time walking around looking at likely sites for hides and clues than I do caching, and more time researching ideas than solving puzzles.
Another reason is that I also enjoy solving puzzle caches, but more importantly I often enjoy not solving them. To clarify that last point, I will use the original "'X' Marks the Spot" cache by purple_pineapple as an example. I spent several months looking at this cache and searching the internet before hitting on the solution. However, I learned an awful lot about local history and some very interesting people, and I feel much richer for it. It also spawned a series of caches in tribute to the original XMTS cache and the inventors of Surrey, of which I have set four, and have more planned. XMTS III has some interesting fact and folklore connected to it, and this in turn got me into researching other folklore for use in caches. For example it is highly unlikely that I would ever have heard of "The Buckland Shag" or "The Rabbit Woman of Godalming" without some of the local puzzle caches I have done and set. As an aside, the latter of the two examples is a true and fascinating story (albeit a little worrying) and well worth reading up on. There are countless more stories, both myth and fact that I won't mention as they are likely to be involved in caches in the future, and yes they will involve research both on the internet and in the field in order to find the cache, but I promise that you'll learn something from them.
I enjoying finding caches full stop. I do however get more satisfaction from finding a puzzle cache, because I've put more into it, and as has been previously mentioned, it is something to do when not actually out caching. There is also an element of getting your own back on other local cachers who have stumped you, as Alboy has mentioned above, but that does not preclude anyone else from getting involved in both solving and setting them. Without puzzle caches such as the Pitch Series, I would not have spoken to a number of people I now class as friends, even though some of them I've never actually met yet!
There are indeed a lot of caches round here that require research before setting off into the field, but there are also those that provide puzzles in micros that can be solved with a bit of thought and no need for the internet, and plain caches where you can walk straight to the coordinates.
I believe that we are really lucky around here to have so much countryside and a variety of open spaces, and the fact that they are packed with caches of all varieties makes us even luckier. Big respect to all the landowners round here who keep giving permission for them. There is a risk of the place getting oversaturated, and some would say that this is already the case, but there are many places around the country where the caches are few and far between, thereby involving much driving before caching. The more local caches and cachers there are the better.
Cachers come in all shapes and sizes, and enjoy different things, and that's the joy of it. We are not all going to enjoy the same things, and puzzle caches are for a certain type of cacher. If caches were cars, not all people who bought a sports car would do so simply to show off or impress their neighbours. Some people actually buy them because they like them (and no, I do not own a sports car). Same with caches, if you like puzzle caches, that's what you're going to set. This is always going to be a subjective discussion, as it's horses for courses. [NOTE - if you skipped straight to this paragraph, then you've missed out the bit on "The Rabbit Woman of Godalming."]
Nanny
PS. Here's a convenient gif for local puzzle cachers.