Well, Mike...
I am not saying you aren't to be commended for not being a lazy twat.
I am not going to disagree that obesity, in and of itself, should not qualify for the blue tag.
I am saying that to deny those who really should need that parking spot is an asshole move by someone that
1) Can't park for shit
2) Can get in and out of that contraption and likely should not be parked there, no matter who did it.
If that is the shops contraption, why not park it out on the grass, up on a rock showing all a little of its capabilities? Why not choose a spot that ain't marked as special needs? I guess it'd be ok if they had modified a short bus.