This is the 13152nd most frequent Turkish word.
kasetçilere
"To the cassette sellers."
Here, 'kasetçilere' means 'to the tape sellers' (indirect object indicating the target of the action).
Eski müzik kasetlerini kasetçilere götürdüm.
I took the old music tapes to the tape sellers.
In this sentence, 'kasetçilere' is used to indicate the location to which the action is directed.
Kasetçilere giderek nostaljik müzik aradık.
We went to the tape sellers looking for nostalgic music.
Here, 'kasetçilere' indicates the recipients of the action of selling, marking the dative case.