or wait for the owner and force him to open the door. There are multiple ways for the criminals especially if they don't have to fear any resistance. Let's face it, the risk for home invaders especially in the UK or Germany is about non existent as home owners cannot or even are not allowed to defend themselves.
Anyway, this is going down the off-topic falls.
We had lock picking in our hacker training class. A normal padlock can be breached in just a few seconds, and it does not even leave any obvious trace.