Jesus didn't go after crowds.  He used the crowds as an opportunity to teach his disciples.  He spoke to the crowds as much as they could understand and explained deeper things to his disciples.

Jesus' primary focus in his ministry was to preach the word.  In fact, his miracles were more of a hindrance than a focus - it distracted him from preaching. 

Mark 6:52  Lack of understanding creates a hard heart. 

Many in the crowd Jesus taught lacked understanding.  To a great extent this was Jesus' intent.  He knew if they understood there hearts would soften and they would turn and be healed.

Jesus must have focused his ministry in marketplaces.  Many people brought their sick to the marketplaces because they must have known Jesus was going to be there.  A simple answer would be the marketplaces is where the people were during the day.  What are our modern day marketplaces?  Paul also taught in marketplaces as well as schools and synagogues.

Mark 5:17 Some regions are evil. 

The people pleaded with Jesus to leave their region, not because of the loss they had with the pigs, but because they knew Jesus was performing righteous acts.  This is confirmed by the demons pleading with Jesus to stay in the region.

Mark 7:8  The Pharisees want to Kill Jesus

Jesus makes a bold statement about the requirements of the law that the Pharisees are breaking.  In fact, Jesus says, "Anyone who curses his father or mother must be put to death."  If the crowds turning to Jesus realized that the Pharisees are dishonoring their fathers and mothers they could turn against them and demand they pay the penalty - death!

The people praised God for giving such authority to men. 

Do we use our authority that way?

Do we feel empowered (authorized) to drive out the demons in the lives of people we lead?

How often are we using our "authority" to pray and heal?  To rebuke and command evil to flee from disciples?