https://www.rei.com/c/bivy-sacks?r=c...y-sacks&page=1
Find a stuff sack or pannier that will hold it with your sleeping bag and pad inside, and you'll only need a couple minutes to deal with a basic camp. Also has the advantage of a very low profile, so if you lay the bike over, everything disappears in tall grass, behind a hedge, etc.
Thieves or vandals are more of a concern for me, but they can't mess with what they never see.