Can you tell?
I appreciate where you're coming from and have had many similar experiences (although I always went for the independent filth of a kebab-van burger rather than the corporate option). I think the problem is that because people are poorly-educated or lack self-control then tend to eat far too much of this stuff (apparently the concentration of such outlets is apparently typically higher in low-income areas too); a situation furthered by the stranglehold such large corporations have on the market through their advertising..
That's just looking at the impact on the individual before the wider effects of their associated health conditions are considered relative to the health service and wider society, or the ethical issues associated with the supply chain or employment model.
Purely from the perspective of instant gratification I could probably happily smash all of McD's products; however absolutely everything else about them I find repugnant tbh.