It's not that confusing for anybody that paid the least bit of attention in school. I didn't know all the nuances of it, but I was well aware that English (as well as most other Western languages) uses the Latin alphabet and Arabic numerals since like 8th grade.

Seriously, the whole bit is just showing how ignorant these people are and how easy it is to frighten them. Like the "ban dihydrogen monoxide" petitions, but for racist chucklefucks.