While I can’t be too sure that this particular customer has “special needs”, I can be sure, since he did exhibit odd speech patterns, and let’s face it, anyone who blurts that out very loud in public can’t have all their marbles.
Then again, he probably wasn’t any smarter than most of the customers I put up with OHH SNAAPPP!!!
Sometimes the helmet can be a tip that they are “differently abled”. It keeps them from hurting themselves. Although, your character’s helmet is not buckled, so maybe it’s because he rode his bike to the store.