Yes, we geocache. Have planted many in close proximity to our cabin. From the logs, which track each find, they are often found. We do have one up in a summit cabin, that has been vandalized, so as soon as the snow clears we'll head back up there to "fix" it, or retrieve it. It has taken us to several places we would not have otherwise found... an example of which is [url=http://www.palmercandy.com" onclick="window.open(this.href);return false;]www.palmercandy.com[/url] That alone is and was enough to... keep us in the game!
This being said, I do believe cache placement could become overwhelming the more popular it becomes. I would hate to find caches when I'm NOT looking for them.
I find it hard to believe that somebody has “stumbled” across enough caches to collect “bags of junk”. Yes caches do get found by non cachers, especially in heavily populated areas, parks, parking lots, camp grounds etc. Usually, but not always official geo-caches are labeled as such, and most who put out caches do so in a manner that they will not be “stumbled” upon. Geo-caches are an acceptable use of the National Forests.