Why are billionaires buy up lands?

[White pawn]

Bill Gates is the largest owner of farmlands in the United States with about 275,000 acres across almost 20 states

Anders Hulsh Pulverson owns more than 220,000 acres in Scotland at the same time the Crown estate which controls about 615,000.

Shouldn't the poor and average people in the society be bothered?

[Charles-Tim]

The poor to be bothered of what? There are still many lands in the world far beyond that. The rich people that you are referring to will have the legal documents of the lands. And if they use the land for farming, it will create jobs among the people and increase employment. It is a very good thing than doing nothing and making the land stay idle without using it for farming.

[decodx]

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Shouldn't the poor and average people in the society be bothered?

They probably should. But what's your suggestion? 

The logic is simple: If you don't own land, you're paying rent to someone who does. The only solution is to keep your land if you own it, or buy some if you can.

[Merit.s]

Why will the poor be bothered when there are other things they need to be bothered of which is how to increase their income. Can you go and buy a Ferrari when you don't have any funds on you.

Land is a good asset and if it's in a good location, it will increase in value overtime. This is why the rich are getting wealthy because they put their money into assets that will generate passive income for them. A poor man can barely take care of his financial needs because he is broke.