Why??

My best guess is, that they don't care if it bothers you as long as their enjoying themselves. I see the same issues in US. Cars driving by with heavy bass rattling my windows, neighbors blasting music on the weekends, etc. So it isn't isolated to only happening here. Music I can deal with for the most part, it's the karaoke that grates my nerves.

I asked my neighbor to lower the music. I said it with a big smile and they did. Since I dont hear loud music from them..  i was told that in the past they make as much noise as they can to frighten the bad spirits... maybe it is the continuation, in modern ways, of an old belief 🙂

How ya go with the roosters  i got 4 ....mate karaoke they love it ....

I have been told that they play the music loud to let all the neighbours know that they have enough money for a party, sort of poor Philippino snob appeal. Roosters, have had a gut full of them at lower levels, now in third floor and above not bothersome.
regards  Bruce

Mostly they just don't care or think about it. We used to do crap like that when we were teenagers in the US - it's basically juvenile behavior, like driving crazy. Most people mature and grow out of it. But here a lot of adults act like that. Sometimes this place seems like the entire population never graduated from high school, and in fact now that I think about it I suppose many didn't.