It really depends on what is cheaper- what will make the better profit. The chemicals that give perfumes their smells are the same whether extracted from natural source or synthesised in the lab- perfume companies decide which they would rather use.
Hi, In order to have the economy of scale, many are synthetically produced in huge reaction vessels and can be manipulated very successfully they tend to be small molecules and can be easily created in bulk and used in a wide variety of ways. They are based on an extracted from natural sources and we replicate these and experiment with these on a tiny scale in the lab to turn one sweet smelling beautiful flower into hundreds of litres in a scale up for mass-production and bringing that beautiful smell to all areas of the world.
Both, perfumes are aromatic compounds which are usually quite volatile. Many of there are extracted from plants (these are commonly called essential oils and can be bought in the pharmacy). while others are synthetic which means there are made in a chemistry lab. Often it may be cheaper to make these compounds in a lab rather than wait for the plant to grow and extract what might be a minute amount of oil and that is the reason it happens that way. The end result is the same, as it is the compound that is in the oil.