Yes, we are living in a desert and they were here first.
When the ground is disturbed over large areas as in new developments, scorpions will be found. A good pest control firm can treat your home and grounds to deter them. Diamondback Rattlesnakes prefer to be left alone and hide under warm rocks instead of invading your yard. In addition to several varieties of the snakes we have of course our own Arizona Diamondbacks baseball team, which we much prefer.