Yeah YANBU.
Something almost identical happened to me the other day.
I was in Asda, (our little one has 12 self serve tills, and no 'normal ones, but an assistant will come and help if you are struggling.)
I wasn't struggling but I had 20 or so items in a big basket. I had a bottle of gin so I asked a lady if she would kindly remove the tag for me. I also had several other things that were awkward to scan. She said 'I may as well put it all through for you.'
Half way through the scanning, this manspreading dickhead, (around 65 y.o.) came and stood RIGHT NEXT to me with 4 or 5 items in a basket, so close to me I could smell his foul breath, I mean like his arm was 3" away from mine, as he hovered around me, huffing and tutting to 'rush me along' so he could get HIS items scanned.
The assistant kept looking up at him and wondered if he had lost something. She said to me (as he gawped into space) 'is he OK?' I said 'excuse me, can I help you?' He completely ignored me, like I wasn't there.
I said to the checkout lady (loudly) 'it's true what they say, when a woman hits middle age she becomes invisible.' She just grinned.
I paid for my transaction, (contactless of course as he was close enough to see my PIN,) and loaded my 20 items as slowly as was humanly possible. He kept jabbing me with his elbow, trying to shove me out of the way.
Unbelievable. What a misogynistic, passive-aggressive, manspreading cunt.
I hope he steps on a piece of fucking lego!