It might make you feel better to know that mayors, especially in small towns, generally have rather low salaries and often work at second, “normal” jobs in addition to their mayoral duties. In fact, the shift manager at the local burger joint likely out-earns the mayor in a town like that.

Also, the scope of a mayor’s job duties can vary a great deal between cities. In some cities the mayor is more of a figurehead, with minimal authority above and beyond a city/town council member.

I have been through Earle (about 25mi/40km west of Memphis) and it makes sense that they would elect an 18 year-old. Like many towns in that part of AR they appeared to be economically struggling, and it seems the citizens have chosen to go with someone young, ambitious, and (likely) idealistic for a change. I would NOT underestimate them.