If your state requires a single keyed deadbolt by law then I have nothing to say so don't even read the rest of this. But if, like Texas it doesn't :
I always put double keyed deadbolts on doors that have windows. That is what I do on the house I live in so that is what I do on the ones I rent out also. I had one tenant request a single keyed lock on her back door that has a window instead of a double keyed one and I got my lawyer to write a lease addendum for her to sign so she can't hold me liable if somebody breaks in and steals all her stuff.
My normal lease states that if the house has any doors with windows (which I try to avoid and sometimes replace doors to avoid) the door(s) have double keyed locks and the tenants have been given an extra key to hide near the door in case of fire. It also says the tenants acknowledge that they are aware of this. It is in bold print and underlined and I make the tenants initial the lease right under that.
It's really not a fire hazard at all unless there are no windows in the room with the door. If it makes you feel better hang a small club on the wall that can be used to break the window in case of fire.
Putting a single keyed deadbolt on a door with a window is about as good as not putting a deadbolt on the door at all. Even leaving the key in a double keyed deadbolt all the time is better than putting a single keyed deadbolt because a potential burglar might not notice the key is in it.