Lately I use a tarp so it is under the tarp for rain protection, but is available to any rodents that might be curious. I do use my pack as an (poor) pillow sometimes. When I use a tent (rarely lately) I certainly do bring it inside the tent. Long ago (ridged frame packs as you may have mentioned) we left them outside with a garbage bag over them. No mice were ever fooled by the garbage bag and on several occasions helped themselves to some gorp or cheese accidentally left in the pack. Okay I guess, we all have to eat.