@lallyk
Oh jeezo, I always forget how seriously these threads can be taken 🙄. To be clear, I was just making a wee light hearted observation at something that I find irritating. Yes, I was a checkout girl too, and a waitress, and a la senza shop assistant (I didn't find any of these jobs shit or mundane though, just jobs) yes, I know some people like to make small talk (so do I, about the weather etc) and yes, I always engage back (would never, ever ignore someone or be rude) but, like previous posters, I want to be able to go to the shop, buy a bottle of wine, a family bag if crisps and a gigantic bar of chocolate and not feel like I need to explain myself! Is that too much to ask?? 😂)
You are perfectly within your rights to feel this way, and ignore the ones who say you are miserable and grumpy, and to get over yourself. You don't owe any checkout operators an explanation on why you are buying what you're buying, they have no right to comment, (or ask you about anything,) and you don't owe anyone any conversation.
And people saying anyone who doesn't want to stay yapping to checkout operators is 'miserable' can bore off. It's got naff-all to do with them if people don't want to talk to checkout operators.
It's not LAW to make conversation with people serving you on a checkout FFS. Be polite and courteous of course, but you don't have to engage in a full blown conversation! If people want to swing by and not speak much, or be grilled over their purchases, they are well within their rights to do this. Without passive-aggressive, underhand, shit from people calling them 'miserable.'
And don't even get me STARTED on the checkout operators making intrusive comments about pregnancy tests, and hair dye, and condoms, and how much alcohol and food people are buying, like a number of posters have said on this thread! That's disgusting. Nosey bastards! 
And it's laughable that people say that the self serve checkout is the answer if you can't be arsed to speak! Every single fucking time I use them, I get a problem that ALWAYS results in someone having to come to the till! The other day I needed an age verification check, for a pack of halls bastard mentho-lyptus !