Is there an advantage to a heater with a ceramic heating body?
According to the Wiki post regarding ceramic heaters, the heating element in this type of device has a positive temperature coefficient (PTC). This means that as the device gets hotter, the power it accepts is reduced, making this a self-regulating heater.

Resistance heaters using nichrome wire or other high-resistance wire are also PTC but according to the same post, the level of temperature required is much higher.

The ceramic heater would have a greater perceived level of safety, although most of these devices have safety features for tip-over protection.

It's possible (but not researched) that ceramic heaters have a higher production cost. It's also possible that these heaters enjoy a perceived high-tech aspect, as resistance (hot-wire) heaters have been around for decades.