Laws (in Sinai)
The Torah Laws, (perhaps including the Oral Torah) which had been given at Sinai, were then obeyed by the generation that wandered in Sinai. Why and how could they obey them, if there, for instance, was no Temple? How could they keep the Laws of Kashrut if they were receiving manna from heaven, that would be by its very nature, kosher? They had no need for work, as they had food and their clothes needed no mending. I wonder if there tents and other materials did.
In a sense the laws were given to a generation who were unable to practice them!
It was only from our entry into the land of Israel that we could begin to obey and enact all of these laws.
Present
Then the dispersal happened, and the ingathering and return to the land of Israel and still no Temple, thus no sacrifices, no high priest, and thus again many of the laws that have been handed down are not relevant to us today—though we continue to repeat them, over and over again, ad nauseum, as if that will make them real.
However, will we go back to an era where we slaughter millions of cows as a sacrifice to G-d? {Interestingly enough, it seems that they are sacrificing millions of livestock and poultry to the god of science.} That is not the stage we wish to live in the coming times.
Livestock
What did the livestock eat during these wanderings in the desert? They were not able to grow, nor harvest grains. Nor did they have need for them - except as animal food. Also the livestock must have increased significantly if no-one was eating the meat. And why would the people not eat some of their livestock, at least, if there were getting bored of eating the magical manna?
The people would also have needed livestock for their transport. Or did they walk carrying their tents and all their belongings on their backs?
Skills
During that period, they must have lost a significant amount of useful skills, as besides having no need of them, they would not have time to set up shop, and teach their children any of their skills. So the bricklayers and potmakers, the leatherworkers and blacksmiths... all were gone!
Thus the generation that entered would know little of such arts. If you think this is unlikely—that knowledge of that nature cannot be not lost in one generation—just look at our children. Children that no longer read books, or know how to do arithmetic, etc. Within one generation think of the skills that have been lost, especially in the move from one technology to another. Try and find a skilled mason today. If we ever need to use horse and cart for our main source of transport, we will be in serious trouble, as there are not enough people who know how to make the leather bridles and saddles, etc that will be needed.
Water
There is no mention of water here either, except in relation to the magical rock that produced Miriam's well. We know it gave enough water for the people's needs, but would it be able to suffice for the needs of the animals that were with them.