Here's an early US mascot suit that you might have seen in a few places. It was in the parade of Jingle All The Way the movie and in at least 1 Toys R Us ad. If it was in a TRU ad, it was probably also used at store openings too, so it would have been seen by many.
But what do you notice about it...is that it's not very good. The head is listed as 'resin', so it would be heavy to use and large to store. The eyes are distorted, the black part isn't an oval, and the 'shine dot' is in the wrong place as well as being unevenly applied. The body portion is fat, and has a distortion on the right bottom area possibly from uneven sewing. It is an early suit, so you can see the back here subscribing to the 'the spikes are 2-d, like felt strips' because it was probably made before Sonic 2 showed the back of their heads. It seems highly likely that the suit is a 1-off, produced by a mascot company for Sega and then seen in a few scenes/ads before they had something else made that was more on model for the character.

What happens to old mascot suits? Sometimes (like with Disney) they get destroyed. Other times, they are warehoused, which was the case with this one until....In this case, it was actually sold to a Sonic collector!