The price of food is relatively volatile, because so much more is produced than is needed, and each food has many substitutes. The same is not generally true of housing. If I decide that the $30/kg steak is too expensive, I can just get the $5/kg chicken instead. Over enough iterations, this gives the beef seller incentive to lower the price, and the chicken seller incentive to raise it, and so they become 20 and 10 instead, and so on.
As well, the lower price of food gives it some volatility. It's no big deal for a loaf of bread to go from $2 to $1 literally overnight, or vice versa; but a house and land won't go from $1,000,000 to $500,000 overnight unless arson is involved, or vice versa unless zoning laws change, or something. Real estate's more stable than food.
This is less true in countries with no real banking and credit regulation, like the US. A lack of regulation of the goods and services in a market lead to price volatility; more regulation, though often onerous, leads to price stability. It might be driven higher, or lower by the regulations - but it's more stable.