That said, I don't think the comments would have bothered me hugely (other than the "spoilt" one), it sounds like they were trying - albeit failing - to alleviate the situation.
3yo DD had a meltdown in ASDA today, total sensory overload (we're fairly sure she has ADHD). Some kids turned and stared at her, and I expected their parents to tell them to stop being nosy, which is what we do with DD when there are tantrumming kids nearby. Nope, the parents turned and gawked too.
If there had been one smile, one reassuring look of "I've been there", even one comment along the lines of "oh dear, what's all the fuss about?", I could have coped. She needed a minute at the absolute most to just breathe and calm down, and I just needed someone to at least look sympathetic.
Everyone around us just glared, so I picked her up, carried her out of the shop (making the meltdown even worse because she needs to not be grabbed or even really touched when they're happening), the people in front of us walked their absolute slowest down the stairs because they were gawking at us too, and once I'd gotten her in the car I sat there and cried. This was people of all ages. Although it was all elderly people in your example, OP, I don't think it's a problem exclusive to any generation. People are judgemental dickheads.