Shopping causes meltdowns!

I have just got in from a trip to Tesco and am still in a complete state due to someone elses child screaming at high pitch non stop round the shop!
I see this is in discussion today on facebook about a mum with her child in John Lewis being asked to leave because her child was having a tantrum, and much is being said about how we should all be more tolerant and non judgmental of such events.
I feel more than qualified to comment on this subject as we had many occasions when Freya screamed her head off while we were out, usually while shopping, and while I don't feel we should have kept her locked up at home during this period I also think you've got to take some responsibility for your child's behaviour and need to consider the rest of the world in dealing with these things.
It can be very isolating having a child who behaves this way and yes people always have something to say about it be it verbally or the way they look at you and there is always judgement about your parenting, it's just human nature unfortunately, but we are in fact not isolated and I have always tried not to let my children's behaviour disturb other people, I just believe it's part of being a good neighbour and citizen to not annoy others.
I fully appreciate that children particularly those on the autistic spectrum can't always help their behaviour but if you know your child can't cope with shopping why would you take them?
Shopping really is very hard for some of us, I hate it still and some days I don't feel able to do it and so I don't, with so much available online these days it's fairly easy to avoid actual shopping.
There seems to be this lack of connection that autistic children grow into autistic adults and I can only assume we're meant to have been cured of our issues with shopping or anything else that bothers us as kids by then?
Well I can assure you nothing has changed, in fact I find it much more difficult now than I did when I was smaller and had someone else in control of taking me, I didn't need to make my own decisions on what to buy, put together meals, work out what I could afford, negotiate crammed isles with blaring lights and noisy beepers going off while often accompanied by 2 small people who also don't like shopping!
My brain is always a mess of thoughts and confusion and add to this the sensory nightmare of supermarket shopping and it goes without saying that I couldn't take the screaming child on top.
As an adult I'm expected to be in control of my autism and to just cope but in reality I really don't have much control over it all. My best option is to remove myself from the situation asap but in this case I had a basket of food and 2 little people running in different directions and by the time I got out I was not far from a meltdown myself. My head was screaming, my ears were killing, even navigating the way home seemed like too much to manage.
It's been nearly 2 hours since I got home and I'm still highly stressed despite taking extra medication as soon as I got in. I have to work this evening and am panicking I'm still going to be struggling by then :(
So I suppose my opinion on both screaming matters of the day is I don't think the woman in John Lewis should have been asked to leave but I do think she should have taken her child out on her own accord as with the woman in Tesco. I wasn't judging her parenting nor do I think either child was just being naughty but as parents we know our kids and we find ways to deal with these things even if that means we can't go shopping with them in tow.
For anyone reading who thinks that's easy for me to say as I had my husband to pick up the pieces when he got home, I was also a single parent for 7 years and juggled 4 small girls round town, two who also had screaming tantrums and I always took them home if they started and god knows I am far from the coping parent!