No, you don't need to say it again, you need to read it again and this time take some notice of grammar and where the full stops are. Here, I'll help you as you're still stoned, here's the relevant section and please, take notice of where the sentences end.
"cannbis will never be legal because it is a gateway drug. the true breeds that are landraces from the good ol days will never be realized if pot was legal. these tobacco and alcohol companies will find the cheapiest way to grow and transport the shit, full of chemicals, pesticides and preservatives to a processing plant with more added chemicals to prep the goods. cancer, health problems, i personally would rather it stay illegal and everyone be oblivious to the laws."
That section refers to the standard reference and meaning of the term 'gateway drug', which is that it leads on to harder drugs.
It's the second section where he puts his 'own' spin on the term 'gateway drug' and uses it in a different context to the way he used the first one, and gives a second interpretation - his own interpretation of the meaning of it.
End of English Grammar 101.