Because I work in a shop and am generally tolerant of people it's the things they do when I'm at work and therefore in a bit of a hurry and other people are involved. Like putting all their shopping down for me to scan, waiting until half way through and then disappearing for a 'few last bits' without apologising or asking if it's okay. They then leave me with a bag full of scanned produce, no sign of them, and a fast growing queue wondering what the hell the hold up is.
Also people who ask for cigarettes as though I'm psychic. 'JPS please'. JPS, what? Red, blue, green, king size, superkings? And then look at me funny as if I should already 'know' (I do, with my regulars, but if I've never seen you before I don't. I'm not Derren fucking Brown, am I?).
When I ask (reluctantly, you have BEEN in a shop before, haven't you?) if you'd like a bag, sneering at me and saying 'well, I can't CARRY it all, can I?' I don't know, you might have a bag in your pocket, your partner may be joining you to help, you may, quite rightly object to the fucking obscene amount of plastic bags about and want to manage without?
That was cathartic.