Strikes are more objective based gameplay, and the objective is the end boss. I think you are a little confused about that. Patrol is the perfect place to take your time and kill every enemy you come across. Strikes are just not designed for that. Yes, those low level enemies are there, but really it is just because you share that space with others that are on patrol on that map. If you really want to take your time in strikes you should play with friends and not randoms. The majority of us just want to get the strike over with and on to the next.