I don't understand the concern?
It's GOOD it's not so simple to lock the door and you need a key.... A) you keep the key safe and B) you don't lock yourself out.
I can see that but it means I need to lock the door with the key when I come *in* to the house as well. I always lock the door with the key at night when I go to bed but if I'm at the other end of the house during the day or doing something in the garden then having the door locked whilst it's closed is just good practice, isn't it?