The 1st Encounter our Lord Jesus christ had with the multitude seemed a pleasant one with the 5 loaves of bread and 2 fishes ,they saw Jesus as a Provider than as a saviour of sin!
Food became more important than the Word of God!
The perishable food sought by an perishable man was not enough to save them from their sin!
The question now is why do people come to Jesus christ?
do they come to be saved from their sins or do they come for other frivolities and pleasure of fleshly desires?
John 6:24-27-ye seek me,not because ye saw the miracles,but because ye did eat of the loaves,and were filled?
This is the attitude of most christians today and that is why spiritual meat(word of God) is more important than physical food(what man desires to eat,hear and do) that is vain &unsatisfying.
in verses 33,the Israeli people saw christ as a normal person and not as a son of God.so they took him physical than spiritual.
for the bread of God is he which cometh down from heaven, and giveth life unto the world.
Jesus said

I am the bread of life;he that cometh to me shall never hunger and he that believeth on me shall never thirst.
so what is hunger and thirst today?
it refers to that vacum created by sin in the life of mankind.it is the curse that brings death.mankind living with sin can never be satisfied because of sin.no matter the achievements,the success, the money.man has no peace,joy,love,temperance,patience,meekness,goodness nor longsuffering against such there is no law.Think about making it on the outside,being popular,and rich but inside of you is sorrow,fear,jealousy,hatred,lust,evil thoughts.if u r a giver with all u got,whats the essence when u r not saved?
whats d essence when u get duped,when u reap sin and the wages of sin?
There is a hunger in you and that is what christ has come to fill permanently.
it is by believing on him and in him that we have eternal life.we serve the creator(God) than the creature(satan)or things in the world that gives us no peace,hope or eternal life!