im not for sure on this, but i THINK it means this...
Mary Jane said life's a wait
I already knew (i guess this means that the marijuana sort of puts you in a certain state where it's a sif it's saying to him 'life's a wait'..as in, you're whole life you're just waiting. you might as well do this stuff)
Because we're down (usually when you smoke pot it's coz you're feeling sad so 'because were down')
We'll lose the town (you smoke pot and you just lose it and forget about everything)
Just like I would choose (just like he wants to)
Mary Jane said minds are games (people just play games and take avantage of you)
I went to the moon (i guess taking pot you feel like you're 'on the moon')
Before we know
She'll have to go (the feeling of pot will fade away)
Wish I were too
But I've got to go (im not sure about this)
Mary Jane (x8)
Mary says
I can love you (you know when you're addicted to weed..let's say you see it lying on the table or something and you really want it...it's like wanting love...so it's as if the girl/pot is saying 'i can love you, so take me'.
Life's a wait
Why should I lose (why should he waste his time waiting? he should just do what he wants)
When I've got to go (still not sure about this)
umm..tried my best...throughout all of this, you can tell the reference to a girl somehow.
Wow, you're good.
By the way, I think the part about the "I've got to go" means something like, there's nothing he can do if the feeling of the pot is fading. something like that probably.
Oh well, guess no one can interpret the song as good as craig can. We should write him a letter.