"and provisions, too, they could not make for themselves": to apprise us of the eminence of Israel. They did not say to Moses: How can we venture into the desert with no provisions for the road, but they believed and went after Moses. Of them it is stated in the Tradition (Jeremiah 2:2) "Go and call out in the ears of Jerusalem, etc." What reward did they receive for this? (Ibid. 3) "Holy is Israel to the L–rd, etc."
Provisions, Too, They Could Not Make for Themselves
Mekhilta Tractate Pischa 14:14