I am currently planning a hike on the Tour du Mont Blanc because I found the idea of a long-distance hike at high altitudes in the mountains very appealing.
However, the system seems to be designed (by making bivouac illegal (like Switzerland or Italy below 2500m)) to force me to pay for nights in a refuge. While I wouldn't mind paying to stay in a nice place in the mountains, I am a student; with the prices averaging 50 euros for a night, a week-long hike could easily use my budget for a month (counting food, transportation, etc). I am really avid fan of nature but I quite simply cannot afford to sleep on refuges every day.
Are there any long distance trails where bivouac is allowed or tolerated in at least a good part of it? As I said, I wouldn't mind staying 1 or 2 nights in a refuge during a week hike (I would actually want that to recharge from time to time), but the prospect of setting a bivouac and being fined what would mean a semester worth of money is scary.
Any suggestions? I have a preference for the western part of the alps (France,CH,Austria).