Well, yeah. They could drive a bulldozer through the side of the garage, too, but it's not likely to happen. More often than not it's a crime of opportunity - if they can't get in quickly and easily they're going to move on and try somewhere else.
Precisely the point. People breaking in through the garage have it in their mind to go through the garage. If they waste time trying and it doesn't work, they're not going to spend any more time finding another way in because they've been there too long already.
If someone wants to break into the house, at least they're still not getting OUT through the garage, which still makes it harder to walk off with a tool box or anything they can't easily carry in hand.
FWIW I don't think security should stop at the garage, and mine doesn't, but I do think it pays to take a reasonable level of precaution. Some people will call you paranoid, some will call you adequately prepared. It all depends on how much risk you think there is and how much deterrent you believe is worth spending time and money on.
As I'm fond of relating, my neighbors live in fantasy land. Some in particular have a garage full of tools and leave the doors up all hours of the day and night with all their toys in plain site. They NEVER lock them, even though they set the alarm on their cars religiously. The same people leave to run errands and they leave the door rolled up until they get back 20 - 30 minutes later. It's only a matter of time before they get hit and hit hard by some opportunistic thieves, or God forbid, something worse. What really gets me is that these are the same people who gave me grief for not joining them at the neighborhood watch meeting to learn about how to protect your home and family. Same people who let thier young kids play in the street on a blind corner after dark too. Go figure.
