Discussion of additional prepositional language concerns what a particle contributes to the relation between a verb and another participant in the event. Sometimes it strengthens the link; sometimes it belongs to an established idiom or construction.
«يَوْمَ يُحْمَىٰ عَلَيْهَا فِي نَارِ جَهَنَّمَ»
“On the Day when they are heated in the fire of Hell.” (al-Tawbah 9:35, excerpt)
The preposition in “ʿalayhā” helps convey the relation of the heating to the objects concerned. A translation may render the total action more naturally than a word-for-word gloss, but that does not mean the Arabic particle contributes nothing.
The interpreter examines the verb’s usage and local context rather than forcing the same explanation onto every preposition.