I don’t think that saying McD has little nutritional value is “snobbery”.
I’m no expert but it seems like common knowledge to me that processed fast-foods like McD contain less “goodness” than fresh foods. What do I mean by “goodness”? I don’t know really but I guess vitamins, minerals, and fibre spring to mind.
The fact that people (including McD themselves) recommend eating it as only part of your diet would also seem to support that.
I personally eat McD once or twice a month on average and so do my young children. I don’t think it’s any worse than any other fast food.