I submit that the answer is... it depends...
For example, if you are 'height challenged' like me, you may (again like me) have an ample belly. This makes wearing a money belt or under the waistband wallet contraption hot, sweaty and uncomfortable, even though it is the all-around safest option. SYates and the other 'skinny' veterans are correct.
OTOH, the belly bag or fanny pack worn around the front brings added volume and convenience. You can also tote all your valuables into the albergue shower and hang the bag near you, always in YOUR eyesight and grab range. This also helps to balance weight to shift some of it from the back to the front.
Finally, my personal solution is to wear zip-off nylon pants with a LOT of pockets. My national passport and pilgrim credencial, along with an ICE (In Case of Emergency) notice in three or four languages), and emergency money / credit card, ride in an aLokSak heavy duty 4" x 7" ziplock bag in one pocket of my cargo pants. My smart phone and other valuables ride in the other cargo pocket. If ALL else is lost or stolen, I can recover with just this one small bag, an a trip to the nearest Decathlon.
See them here:
http://loksak.com/aloksak/
Other needed items are arrayed about my pants pockets. For examples, I carry TWO Buffs, one to each rear hip pocket, where they do double duty as butt-pads when I sit down. These weight virtually nothing, but can be used for a myriad of things beyond just wearing.
I have used Buffs as an expedient compression bandage to staunch bleeding from a head wound (I fell over a fence), a face and hand towel, a means to attach my hiking poles to my rucksack, etc. Uses for a Buff are limited only by your imagination.
One year, I even met a group of runners, doing the Frances in reverse. They carried NO packs. Each person had the taffeta weight running togs they were wearing, one light shell jacket, and watch cap, and a Buff. The Buff was their bath towel - they were very thin people....
In an albergue situation, these pants go into the shower stall with me. I pack a small but strong "S" hook to support hanging my "loaded" pants nearly anywhere.
Also, and just as an FYI, If the lower pants are soiled or wet, I merely zip them off, wash them separately, then rinse, roll, stomp and hang them to dry.. It usually takes less than 45 minutes for the 100% nylon to dry enough to reattach.
Hope this helps.
