Because Sonic Team has no clue as to what they're doing, so the Sonic fan base is ridiculously fragmented. The fans act as if the stories in Sonic games are important. And it's filled with yiffers. Just check out the Sega forums.
Here's a link: http://forums.sega.com/forumdisplay.php?42-Sonic-Games
Yes, the story whores are ridiculous. I hate that fragment of the community. They want a in game explanation for every minor detail; Who gives a fuck on why the moon is still not destroyed since SA2. Can you believe people actually care about that?