You may not act that way but others certainly do. Populations do tend to act riskier when they have better safety equipment whether it's seat belts or ABS and by extension PLBs.

See for example: http://en.wikipedia.org/wiki/Peltzman_effect

I would like to think having a PLB won't change anything but I have also found myself saying to myself, "I would feel more comfortable taking that solo cross-desert drive if I buy the PLB" In other words, it does enable more risky behavior just as the ability to use a cell phone in the wilderness does.

The converse is also obviously true. Imagine how safely you would drive with a 10" spike mounted on the center of your steering wheel.

There are also many corollaries. People with little chance of outside help also devote a huge amount of resources to preparedness (such as an Apollo mission) and if the chance of rescue is high -- such as in a city drive to work, you don't devote nearly as many resources or demand as much safety equipment.