I think the McLibel case turned lots of people against McDonalds. Trying to stamp on the little guy never goes down well, nor does hiding evidence. It was a public relations disaster.
I think that thier refusal to accept any responsibility for the increased litter near their restaurants is a bit off too. If the locals complain because there are empty Maccas packages everywhere it's not too much to ask that at the least you acknowledge that there is a problem.
McDonalds is the world's largest user of beef and they also sell more toys than any other company on earth and most of those toys are pretty much disposable so there are concerns over their environmental impact.