Buying Hebrew servants?

Exodus 21:2 says, “If thou buy an Hebrew servant, six years he shall serve: and in the seventh he shall go out free for nothing.

21:3 If he came in by himself, he shall go out by himself: if he were married, then his wife shall go out with him.

21:4 If his master have given him a wife, and she have born him sons or daughters; the wife and her children shall be her master's, and he shall go out by himself.

21:5 And if the servant shall plainly say, I love my master, my wife, and my children; I will not go out free:

21:6 Then his master shall bring him unto the judges; he shall also bring him to the door, or unto the door post; and his master shall bore his ear through with an awl; and he shall serve him for ever.”  I thought they had just survived the exodus from Egypt, but why would they be buying and selling each other so readily?  It reads that if you are a girl sold into servitude it is forever.  That would be slavery.  Why would god tolerate this?  Women have no value in this book once again.  Why would any of these people need servants?  They just got all that wealth from the Egyptians a few months ago.  Exodus 12:35 “And the children of Israel did according to the word of Moses; and they borrowed of the Egyptians jewels of silver, and jewels of gold, and raiment:” Shouldn’t they all have money?  They have free food (Manna.)