There are sprays out there on the market that are typically much more affordable than these types of devices, but they come with a few drawbacks. The first drawback is that they are great for using outdoors because you will be reapplying a new coat every time it rains. With these devices, you can simply place it into the ground and let it get to work with very little input from the user. Another drawback has to do with its effectiveness. While many think that it is a good solution to work indoors, many have found that it isn’t effective at all when used outdoors due to rain and competing odors found in your lawn.