Moses and the Israelites have been wandering in the desert for 38.5 years.
They’re complaining, just a little.
(Big surprise, eh?)
They’re basically tired of wandering, perpetually lost, hungry, and thirsty, and bored with the limited menu: namely manna, quail, and water from a rock. Perhaps a little variety would be nice: maybe some salmon? a nice green salad? would a little fruit — some strawberries, or perhaps a handful of grapes, be too much to ask? all washed down with a nice, under-oaked Chardonnay?
ANYway, God hears enough of their incessant whining, and sends poisonous snakes among them. (Let THAT be a lesson to you.)
I can honestly say, in all these years of having children complaining about what they are being fed for dinner, I never thought of this.