I agree. Leaving doors unlocked may be fine in your neighborhood 8 or 9/10 but why take that risk? Always deadbolt and always make sure everything is locked and secured before bedtime.
It doesn't hurt that I have Achilles who barks if anybody even steps close to my property. He is a 60 lb Aussie though so he is only a detection helper.... Although I taught him the difference between invited guests and strangers so I have no idea how he would react with somebody forcibly breaking in the place while I was sleeping. I'd rather never find that one out....