The costs will go up, and it's a pain in the ass generally. If you get a false alarm, then you get a big bill from the cops. Or you can save that expense by forking over a regular amount each month to have any alarm checked by a security guard that works for the company before there is any call to the cops.
It's a trade that is based on fear, and the cost just doesn't have to necessarily reflect any level of service. Working out of our home, we were able to write off the expense, but I ended up canceling eventually anyway. We still have the stickers on our doors, so if the idea of an alarm brings about any avoidance, we get that for free.