People blame God because they believe that God is responsible for the wrongs that we do and that since he is God he should protect us at all times, forgetting that we also should learn to guard ourselves against Satan and his evil ways
God does not tempt us, the Devil does but God allows those temptations to happen to see how deep our faith and trust in him is.
Sinful people, I believe , the enemy already has them in his side and there is no way God will tempt them because they already allowed their hearts to fall into the trap of sin
If God did not allow people to sin then there will be no free will - God wants us to be able to choose him out of our own free will.
God allows evil to exist for the purpose of knowing who His true followers are as they will choose him over evil.