It's not app's cache I believe, but rather app's data. I think they're different? It's indeed 39MB on Play Store, but after I installed it and used it for a month, it's using 1GB+ storage on my phone (after I deleted app's cache).
Ha, I hate it when apps do that. One of the main reason I got rid of Spotify and my Spotify paid subscription was because their android app gobbled all the free space it could find on a device by filling it with caches music. “Of course Spotify, I pay extra for more storage on me device so you can use it to cache songs and save a few cents on bandwidth, you’re very welcome.”
I’m not talking about being able to download an album actively. I’m talking about Spotify using up all my devices storage to store their own cache, songs I listened to but didn’t select to be downloaded for offline listening.
Ah, fair. Though to a certain degree I still think that's helpful when I recently listened to something but forgot to download it.
I agree though that that shouldn't take up all of your storage and should definitely be toggleable.