it doesn't express a decimal point if you think of cents as a completely different unit of currency from dollars, but if you think of cents as 1/100ths it actually does indicate the decimal point. "5 dollars and 13 100ths" which is what cents means, and which is sometimes used when not referring to money, for example items that are measured in centiles such as interest rates. I think our forebears were more likely to throw words like centile around, and thats how they came up with the word cents.

My cousin is Italian and he always says "for cent" to me and I scratched my head till I realized, per is translated to for from Italian, and they say "25 per cento" so he's just translating it to English as it makes sense to him, not realizing we also have the word per.