The film industry suffers from the piracy that is rampant in China. A lot of pirated films end up in torrent sites. This makes hollywood lose money, so they would rather make sequels since these do not need any new creation and they would just use the existing assets to make a film.
Aside from that, it also seems that movie goers nowadays have lost their appetite for original works. 
Thus from all sides, it is cheaper to make sequels.
What really annoys me is the fact that films don't have music anymore.
Everyone have seen me complaining here about LoS' soundtracks, but that is mostly because I consider it generic and boring for being a Castlevania, because I consider CV 1986-2008 the best music ever done. Better than any band, any composer, anything, EVER.
But... and this may come as a surprise for many... Araujo's compositions are in fact better than today's move standards (and with today I mean the last couple years).
Sure, from time to time we have soundtracks like Solomon Kane out (I believe it's from 2010), but almost all films have completely boring "soundtracks". WAY MORE BORING than LoS.
I watched The Wolverine on last weekend. And while the movie was very good, it didn't have music. Really, just pay attention and try to follow or understand what's going on. It's just random chords with no form whatsoever, no melody, nothing. We've always had parts that follow a certain scene that, as music, didn't make much sense. But every soundtrack used to have the main theme from the movie, character themes, and a lot of identifiable melodies.
Remember Pirates of the Caribbean saga? It's not been SO MANY years since that. But movies have completely lost their soundtracks.
What's the theme for The Wolverine movie? It doesn't have a main theme. It doesn't have a proper theme. AT ALL. In all the movie.
And that applies to almost every movie that comes out from Hollywood today (this still doesn't apply to european or korean movies, luckily, I don't know about the rest of the world).
I had to say it, I was very annoyed about the soundtrack and I want to know if anyone feels the same.