You're basically asking to lose your car when you do something this dumb.
First, the good news. The National Crime Insurance Bureau (NCIB) has announced that overall vehicle thefts are dropping. The bad news is that more and more cars are getting stolen due to people leaving the keys inside of them. From 2012 to 2014 a total of 126,603 cars were stolen with the keys left in them. In 2014 alone a total of 44,828 cars with the keys inside were stolen, making up 6.7 percent of all cars boosted. California leads the way with 19,597 cars stolen with the key inside.
The NCIB says that the numbers are likely wrong as the only way to know for sure is to recover a stolen car with its keys. It's also likely that some people don't cop to cops about leaving their keys inside the car, while others do it purposefully to claim insurance money. If you don't want to lose your car, stop leaving your keys in it!