Why use Normal Words when you can Make Up Your Own and Sound More Intellectual?

So I have noticed a number of words made up by academics over the course of my degree which really do seem to be completely unnecessary as there are plenty of existing words that when used in combination mean exactly the same thing. So why do they bother to confuse everyone by making up new words? Some examples:

Distanciated - separated in time and spaced i.e. distanced from
Technicist - not really sure what this means I'm guessing technical
McDonaldisation - basically society is becoming more uniform and predictable like every McDonalds in every country
Dramaturgy - Living life like a drama
Actionalism - some sort of theory about actors
Panopticon - a type of prison with potentially constant surveillance
Iatrogenesis - doctor-generated illness

Academics are also guilty of using words to mean different things e.g.

Demoralisation - the decreasing influence of morals in society not the usual lack of morale

They also like to use big unusual words when simple ones would suffice e.g

Cornucopia - a horn of plenty used in the context of having a lot of consumer choice why not just say there is a lot?

I bet you have come accross similar things too (unless it is just the social sciences that are this weird). Feel free to comment with some examples.