It's only recently occurred to me that "must be funny/in a rich's man's world" may be a not-quite-fully-idiomatic-English Swede-lyricist's attempts to say 'rich men must have a lot of fun' (rather than, say, 'tch! funny old world, weath!')
But what it lacks in command of idiom it makes up for in sheer greatness, this song. Here's a small example of what I mean. Take the title line: six syllables sung on two ascending triplets. The effect is to teeter-totter, or seesaw, the emphasis subtly from MONey to moNEY and back again ... nicely, if almost subliminally, disorienting. Because, of course, nobody thinks this minor-key little hymn to the desperation of desire is actually a song in praise of being rich? The opposite, of course.