1. I managed to do business without taking drugs as long as I can think.
2. I am used to people coming to me for advice and my services. I never needed to advertise etc. so THEY will have to do business else where just as I said.
3. Just because in your opinion (data please) "many business relationships are formed from having some drinks" does not lead to "ALL business relationships are formed from having some drinks". This is a flaw in your logic.
4. If "feeling friendly/chatting/etc." is the reason for you to take drugs then I advice you to do therapy or something else to learn to be friendly, chatty etc. without the need to take drugs. If you need drugs to achieve this all the time this is a clear indicator that you have serious issues.