The strange thing is your wife when having a shower will probably lock the bathroom door, or you will, so why dont peeps lock the exterior door to the house when theyre there, just imagine somebody walks in, what are you going to do possibly pick up a kniofe or something handy and hit them,or run and lock yourself in the bathroom.
Keeping the external door keys and the shed keys is a bad habit, you loose the set and your locked out of shed and home, always kep the shed keys hidden and on a large colured tag, so you can see it, its the advice i give my customers.
Sincerely hope you get the bikes back, or replaced.