Are There No Graves in Egypt?

Exodus 13:19-22
(19) And Moses took the bones of Joseph with him: for he had straitly sworn the children of Israel, saying, God will surely visit you; and ye shall carry up my bones away hence with you.
(20) And they took their journey from Succoth, and encamped in Etham, in the edge of the wilderness.
(21) And the LORD went before them by day in a pillar of a cloud, to lead them the way; and by night in a pillar of fire, to give them light; to go by day and night:
(22) He took not away the pillar of the cloud by day, nor the pillar of fire by night, from before the people.

Exodus 14:10-11
((10) And when Pharaoh drew nigh, the children of Israel lifted up their eyes, and, behold, the Egyptians marched after them; and they were sore afraid: and the children of Israel cried out unto the LORD.
(11) And they said unto Moses, Because there were no graves in Egypt, hast thou taken us away to die in the wilderness? wherefore hast thou dealt thus with us, to carry us forth out of Egypt?