When you do 1 by 1 from Lee to Guy as it consumes more coins. When you're at Guy's spot, there is a chance you'd get something good. That's all.

So "Call Guy" is basically skips all Lee's to Guy for a chance of something good. not worth to spend cps.

As opposed to run it by coins, sometimes u won't get up to Guy when you receive grey chakra then it resets back to Lee.