> Finnish 'cases' are more like suffixes like '-ne' or '-que' in Latin. E.g., '-ssa' or '-ssä' is 'in (location)': 'Amerikassa' 'in America', 'Sveitsissä' 'in Switzerland'. In Japanese the ending for 'in' is '-de' and in Tamil, it is '-il'.
This seems to confuse inflectional suffixes with analytic particles. Certainly -ne and -que in Latin are not suffixes; they are clitics, exactly analogous to the English articles a(n) and the (not usually considered "prefixes"). They are not part of the word after which they appear. In contrast, the -i in humi "on the ground" is a part of the word, which mutated into that form to express a locative use.
(As a side note, that is not at all the norm in Latin - location is usually expressed with a preposition, as in sub monte "under [at the foot of] the mountain". Humus is one of only a handful of words that preserve the locative case.)
I believe the situation for Japanese de is similar, with de being either a clitic or a fully independent word. I have no knowledge of Tamil or Finnish.
In Japanese, as in many other head-final languages, it is often hard to impossible to distinguish between clitics and suffixes. -de can only attach to a noun because a noun phrase always ends with a noun and there can be nothing between a noun and a -de, they are inseparable. On the other hand, there is no phonological fusion of any kind between a noun and -de (unlike in verbs, where yom-u 'to read' becomes yon-de in the gerund form). Because of this -de and other case markers are described both as "particles" and "case endings" in different sources.
In agglutinative languages with freer word order, it is easier to argue that a locative morpheme is a suffix because it always appears with nouns, but absent any phonological processes that bind them together, one can always write them with a space and call the second part "locative postposition". In some cases, it is even unclear if an agglutinative language is very morphologically complex or just uses a lot of function words.
This seems to confuse inflectional suffixes with analytic particles. Certainly -ne and -que in Latin are not suffixes; they are clitics, exactly analogous to the English articles a(n) and the (not usually considered "prefixes"). They are not part of the word after which they appear. In contrast, the -i in humi "on the ground" is a part of the word, which mutated into that form to express a locative use.
(As a side note, that is not at all the norm in Latin - location is usually expressed with a preposition, as in sub monte "under [at the foot of] the mountain". Humus is one of only a handful of words that preserve the locative case.)
I believe the situation for Japanese de is similar, with de being either a clitic or a fully independent word. I have no knowledge of Tamil or Finnish.