There is like less difference than you might think. The difference between artificial and natural flavoring comes down to the source material. Both are chemically identical. Natural flavoring is regulated and defined by the FDA as “flavoring extracted or fermented from a spice, fruit, vegetable, edible yeast, herb, bark, bud, root, leaf or similar plant material, or dairy products.”
Artificial flavoring starts with a purified chemical source, but arrives at the same end product: A concentrated, purified flavor extract.
For people with food allergies, synthetic flavoring allows them to enjoy flavors they would not tolerate in their natural form. For instance, someone with an almond allergy would be able to drink tea with synthetic almond flavoring.