You were right about that.
What you say about pot is true of ANY minor wrong-doing, softening one's attitude towards other wrong-doings.
Speeding?
Pre-marital sex?
Leaving the office early (these days, kicking back for a nap early)?
Any of a million "Little White Lies"?
Eating the last cookie and blaming it on your sibling?
In other words, you pick on "pot" as a Gateway Crime" but it's one of a million such.
~ C.S. Lewis