The professional chafing dishes don’t directly deal with the localized burning issue. They typically heat a pan of water, and then have the food suspended above the water, so the food is only heated indirectly.
You can do this with the candle burners, but they’re typically sized for 9x13 pan, so you might need to find appropriate sized dishes that can nest with a gap in between to hold the water.
All of the candle burners that I’ve seen held two candles. Often, it was because there was a device that let you control a flap from the side that could be used to snuff out the candles. I think I’ve put 4 or 6 inside them (its been a few years). The larger issue is that for really long events, you have to remove the food to open them up and replace and relight the candles. Chafing dishes are wide open on the bottom, so you can easily get in there to replace the alcohol or gel fuel.
Some other options that you may want to consider:
- butane or propane powered hotplates, which take bottles of gas. (Easily controllable, but some of the expense issues of chafing dishes; can also be used for camping / when the power goes out to cook)
- place some towels, trivots, or other insulation down, then hot bricks or cast iron griddle, then your food to keep warm. (Can’t control as well, or refresh easily)
- Electric devices (warmers, griddle, crockpots, etc), but tape down the electrical cords. Plug in the cord to the wall, leave a little bit of an extra loop at the wall, then tape it down. Run it as straight as you can across the floor to the table, then take 2” or 3” gaffers tape (5cm / 7.5cm?), and run it straight over the cord, then press it down on each side to secure it to the floor. Gaffers tape holds well (even to short carpet), but doesn’t leave sticky residue like duck tape. Wrap up the rest of the loop leaving your enough to plug in your devices, and tape it to a table leg. (Always leave the extra loop on the table side, in case you need to reposition the table)
- If you’re not going too far with the electrical cord, you can also get rubber devices to run cables under/through (search for “extension cord cover” or “extension cord protector”), but they’re a little more of a tripping hazard as they can be an inch (2.5cm) or so high. They’re less flexible than tape as they’re of a fixed length, but reusable and relatively inexpensive ($10-15 for 6foot (~180cm) sections
- There are also companies that sell integrated extension cords with protectors (such as Electriduct brand’s “Low Profile Electrical Power Extension Cord Cover”). They’re more expensive and even less flexible, but they’re very convenient.