This is likely to be an in-store promotional poster or some type of sign. It announces the first set of Sonic toys McDonalds had in the Happy Meal. It says "Collect All 4! A different one each week" The bottom small text explains how you get it free in a happy meal.
Look at how the art is drawn to actually look like the toys themselves, rather than the actual characters. Sonic has a fin of spikes, Knuckles has a giant lower face & very tall head, the Robotnick looks about the same (complete with winder on the side) and the Tails...is a little odd. Yes he's a flat thing (looks sort of long-bodied here like a wiener-dog) but notice how it's not the one that "flew" from the helicopter type ripcord thing but the other one where he rotated the tails as you pushed him along.