The Valley Hostel in Lauterbrunnen seemed a fairly sedate place - family run, and the clientele seemed to be mostly quiet young Asian adults when I was there. I didn't actually stay there - I had confirmed shortly before arrival but they still screwed up my reservation. However, the owner called around and found an apartment nearby that worked out well for us.
As for Füssen, there are many small B&B operations that compete in price with hostels and would surely provide a more enjoyable experience. Here's the local tourist office list of accommodations:
http://www.tourismus-fuessen.de/387.0.html
- Pull down "English" at the top right where it says "Deutsch".
-Under "Area", select "Zentrum" for center or make no selection to see all areas of Füssen. You'll get several pages of accommodations options. Look for "Haus", "Gästehaus", "Garni", "Pension", or just someone's name for the less expensive accommodations - several are in the 20-30 Euro each price range for B&B