Why are not included all the available songs in each TTR new version released?

That could be a good reason, but I am not completely agree with it and Iwill give you another ones.

Anyone that have the enough knowledge (and time) to do what you say, could use another 2 methods too:

1) Access to the filesystem through a Jailbroken iPhone.
2) Access to the filesystem through thirty party applications available at Internet without to do the jailbreak (I would not mention there here, sorry).

So, I continue without see the real problem, moreover, when we are able to download those songs thourgh Tap Tap without pay in any case, anyway.

People have already downloaded the other songs that came on TTR already so why wouldnt that stop them from getting the others? I dont know thats my point of view and its probably the reason why Tapulous did it the way they did. Plus downloading the songs for free on TTR isnt really the same as downloading the song itself to your ipod/iphone because you have that forever to listen tooand even share that file with others. And other side would be that you would have to release a new updated version every Thursday to get the new song and thats pretty tedious and annoying. Tap Tap Thursdays are fun and I think it would ruin that. My opinion although I kind of agree that would be nice in a way but in the end you still have to download something so why not just do it easily on your device right in the app?

The app file size would be so big that it takes forever to download if all the songs were included with an update. It would be no quicker than downloading using the app. And i read about someone who wanted to delete individual songs because of either disliking themor the songsbeing inappropriate for other people to play (kids) so thes epeople wouldnt want them all included.