Is God's favor the same as favoritism?

No. God's favor does not mean He thinks of anyone as better than another. It means that He approves of the way we live our lives for Him. Mary is a good example. God the Father chose her to give birth to the baby Jesus. She was a godly woman who had lived a chaste life according to God's Word. When God bestows favor upon certain people it is because they have lived godly, righteous lives, but that does not mean they are "better" than others.

Notice that the angel Gabriel told Mary that she was "highly favored" and "blessed." This was because she lived her life in a godly manner, not because she was a better person than anyone else.

"Now in the sixth month the angel Gabriel was sent by God to a city of Galilee named Nazareth, to a virgin betrothed to a man whose name was Joseph, of the house of David. The virgin's name was Mary. And having come in, the angel said to her, "Rejoice, highly favored one, the Lord is with you; blessed are you among women!" (Luke 1:26-28)

In the book of Proverbs, we learn more:

For whoever finds me finds life, and obtains favor from the LORD; but he who sins against me wrongs his own soul; all those who hate me love death" (Proverbs 8:35-36).

Further, Solomon taught that we find the Lord's grace and favor by following his mercy and truth:

"Let not mercy and truth forsake you; bind them around your neck, Write them on the tablet of your heart, and so find favor and high esteem In the sight of God and man" (Proverbs 3:3-4).