meaning of low spark of high heel boys

Low Spark of High Heeled Boys has a profound meaning
It's a drug reference to a speed ball, a mixture of heroin and cocaine, in early seventies girl meant cocaine and boy meant heroin thus low spark of high heeled boys. The man that was shot dead by a gun that didn't make any noise ,
(Shot from a needle ) what put him to rest was low spark of high heeled boys.

if you don't understand now don't worry to much it will happen to you

I agree that it has a lot to do with the music business. Men in suits promising riches, driving new cars, and keeping upcoming bands on lines of credit. Rock stars living beyond their means as record producers rush to find the next new superstars. The last stanza sounds quite different as Winwood sings “Spirit is something that cannot be destroyed. And the the sound you are hearing is only the sound of the low spark of high heeled boys.” Listen closely & imagine the next two words are slightly different. Imagine a homonym as you hear the passionate upswell of the band…”HEALED boys!” Love this. You can try to screw over true artists, but they have the muse, they have the talent, and no matter what, Traffic has the Spirit!