HMD, how many people on here are still putting coals directly on foil?

I bought an expensive and popular black HMD tears ago, I think it was called the klaud, it didn't work so great for me. I'm reading on some posts people saying that they let the coals heat it up before they start smoking. I didn't do that, but I'm wondering what's the reason people don't want to put coals directly on the foil? That's how all the popular lounges do it, that's how I've always done it at home. What's the benefit of going with a device? I see so many people posting their setup and it almost seems to be a sin not to include one, obviously everyone has the right to do what they want. But what I'm wondering is, what's the big benefit? Is it just a phase or a trend, or is there actually a benefit to using these things?