Any number of reasons. The most obvious being "they plan on using it at some point". It doesn't mean they're using it now, though. If they are, that's a problem obviously.
If the data is being scraped and stored locally, they don't necessarily have to ask authorization. Videogames don't have to ask permission to create a log file containing your OS, Windows Location, installed drivers, CPU details, GPU details, and stuff like that. They DO have to ask permission to send this data back to the game's developer.
I wouldn't put it past Epic to at some point confusingly ask whether you would like to not not not not not not send data about time played to Epic, however.