"The examples give so far seem to confirm my original impression"
Well, Joe F. 'That Acapulco Gold' that I mentioned earlier is most definitely celebrating pot smoking.
Me and Martha took a honeymoon,
Below the border 'neath the silvery moon,
She was eighteen and I was twenty two,
Now we're just a-doin' what the old folks do
We're goin' south, south, to get that
Ain't nothin' it can't fix,
Old dogs can learn new tricks,
When the streets are lined with bricks
Of Acapulco Gold
We 'bout decided against the whole thing
But then we thought we really ought to swing
Heard that the south land held the key,
To cure them cotton pickin' sniffles and sneeze
Zig zag, white or wheat any'll do
Hey diddle diddle twenty three skidoo
Me and Martha sure had fun
Now there's Acapulco Gold for everyone
BTW, someone mentioned 'Let's Go Get Stoned' but that is clearly about alcohol. He even mentions buying a bottle of gin.