Why? Because they are big, layered flavours that in the hands of a skilled mixer can bring an otherwise interesting but uniform flavour experience to life! Some of the most amazing eLiquid flavours of all time have been 'tobacco' based- RY4, Longbottom Leaf to name just two.
When smokers switch to vaping a lot of advice suggests starting out on tobacco flavours and then "graduating" to other flavours over time. This assumes that a recently quit smoker is looking for something that emulates the experience of smoking. We don't actually agree with this- smoking is a pretty poor substitute for vaping... that is how vaping helps people to move on- by tempting them away with something better. More interesting. More flavourful.
But tobacco flavours do have something going for them. They have wide and enduring appeal for a reason- that reason is that they are amazing, classy, beautiful and bold!
Fortunately the process of applying these flavours to vaping strips them of their most dangerous properties- their association to combustion gases and tars- leaving only their flavour appeal.
And there are some staggeringly beautiful flavours that tend to be classed as tobaccos- interestingly they are uncommonly actually in tobacco products at all. They are, almost all of them, flavours that professional flavourists feel will emulate, evoke or resonate with the rare flavours that do come from this domain.
Many vapers- including us- continue to enjoy their deep complexity; the body and satisfaction only this class of flavourings can deliver.
Don't be afraid of them. Try them and choose your own direction.