It seems tobacco companies have been using sugars, (caramelised by the heat), et al. for many years.
It is claimed that Marlboro kicked this process off, as not only does it allow for greater absorption of nicotine, (allowing them to use lower grades of tobacco, whilst increasing their profits), but the sugars create a secondary addiction, (read "brand loyalty" in this context).
This potentially explains RY4's successes
https://cebp.aacrjournals.org/content/27/3/357.1
It is claimed that Marlboro kicked this process off, as not only does it allow for greater absorption of nicotine, (allowing them to use lower grades of tobacco, whilst increasing their profits), but the sugars create a secondary addiction, (read "brand loyalty" in this context).
This potentially explains RY4's successes
https://cebp.aacrjournals.org/content/27/3/357.1