Scent really has a large market. Poeple use scent for home diffuser;Use scent for car diffuser; Use scent for message;Use scent for body. In fact scent has two big categories.
1. Fragrance which made of chemical material.
Even all made of chemical , fragrance price also has large different. Because people will use cheaper material to low down the concentration of fragrance.
For car and home diffuser ,the fragrance is the cheapest. Then the scent for soap making kit and candle making kit is a bit of expensive as it need higher concentratin than the one which need be melt in water.
2. Essential oil.
In fact essention oil has much price different also . As the real original essential oil is really expensive as it just can get small from large plants. So people will add the basic oil to make it a little cheaper.
Check the ingredient of scent oil to see what it has. Normally will know what you get.