Snoop Dogg's use for the lighter is already covered by "and more" before it gets to Willie Nelson. What is the "so much more" he's doing with a lighter that doesn't involve grills, candles, or smoking?
Willie Nelson is known for using his for an extended quantity. Which is where the joke is, here. Snoop is known for smoking weed, and Willie Nelson is known for smoking a substantial quantity for longer than Snoop has been alive. For comparison, Snoop is 52. Willie is 90.
I was going to say I think there was a smoking contest between them.... But it was Ricky from trailer park boys vs Cheech (or Chong? For some reason I can't remember right now.)