This abomination would be worth it is one thing happens:

Post-credit scene: Sonic chomping down on a chili-cheese dog like a goofy-ass-looking schmuck minding his own business. An inter-dimensional rift opens up nearby (cue screams coming from people all around the area.) Sonic says something quippie to the hot-dog-stand-guy about being back before you can say, "Hey, you have to pay for that." He is about to wind up into his little zoomy-ball form and meet whatever threat is coming through the portal, but bends down to tie his shoe.

While he is bent down, a red lighting-ball zips by the hot-dog stand and knocks the umbrella over. Then it zips back the other way, across the street, spooking a flock of birds into flying away. Sonic winds up his speed-ball and takes off after the red ball. After a brief chase the two speedsters end up right back in the park that they started, near the rift.

The red ball stops. The music begins to build to a crescendo. A short, burly red echidna with his arms to his sides looks up at a man behind the counter of a newspaper stand. They can barely make eye contact because the echidna is so short, so the man leans over the counter. With a thick Ugandan accent the red creature utters the words, "Do you know dey whey?"

The camera pulls back. The headlines of the newspapers read, "Global Ebola Outbreak Worsens!"

Camera keeps pulling back.

We see Sonic across the street, staring in disbelief. Mouth wide open. Music reaches its peak, almost deafening the audience.

Cut to black.