Shopping addiction may be  defined as  constantly making new purchases of unnecessary or superfluous things.
a Shopping addiction is very hard to control! Any advice on how to control that?
Sure it is ,its a deficiency of impulse control which appears as the eagerness for constantly making new purchases of unnecessary stuff.You may call it spends rift
I assume it is not hereditary?
Not really but a a concept similar to "compulsive buying disorder" and "oniomania", although these terms usually have a more clinical approach, related to a psychological individual disorder 
Do you know how many people are affected by shopping addiction?
No! There are three kinds of behavioural manifestations of shopping addiction, 
What are the three kinds?
First is the attraction towards the consumer stimulus, which is the addiction to purchasing as a leisure 
Any other information you can tell me?