I myself was thinking of the GOTY edition. Furthermore, I believe UC3 was bundled as early as the games release, and Gears 3 also had bundling.
UC3 and Gears 3 both had launch bundles. UC2 was actually bundled after launch with the premium PS3 SKU of its time.
And yes the huge spike is due to the GOTY bundle (and UC1 and UC2 got a similar bundle during the last holiday and saw a similar boost).
I'm not saying that it's impossible for UC3 to eclipse Gears 3 at one point (without bundles) but you could at least ask yourself why UC3 jumped to these hights lately and do a bit of research before creating such a thread.
Threads like this will only lead to copycats making threads about Kinect Adventures is a bigger franchise than Gran Turismo or other similar crap which we don't need.