my diabetic dad has been given full sugar coke instead of a diet one too.
And fucksake, if you're diabetic or otherwise needing sugar free syrup, you don't order drinks with syrup in!
Eh? Was that a response to the top comment? Why wouldn't you order a sugar-free syrup drink if you need sugar-free syrup?
I haven’t drunk fizzy pop at all for years now, but I used to be addicted to Pepsi Max (hence finally completely giving up). I wasn't fussy if they only had Diet Pepsi, Diet Coke or Coke Zero at pubs, but I’d estimate that at least 30% of bar staff would pour normal full-sugar cola of one variety, having been clearly asked for diet. Like the OP, I would have to watch them carefully to see which button they pressed on the pump, as so many would just press normal Coke/Pepsi. I tried to be discreet in watching as I'm sure it would be very annoying for the many bar staff who were capable of listening and serving the correct drink as requested, but the huge minority made it necessary to watch them. They would almost always huff too when asked kindly to swap it for the ordered drink, as if it were somehow my fault for being difficult, and very few would offer a cursory apology.
It’s all very well people complaining that customers patronise them and don’t trust them to be able to do their job, but if they don’t know whether you might be in the 30% or so who clearly can’t do their job, what else are they meant to do? Nobody would object if you didn't hear or doubted yourself and asked “Sorry, was that regular or diet/normal or decaf?”
In the end, I exploited the many diet variants to my advantage – and the fact that, although many bar staff wouldn't care about giving you sugary when you’d asked for diet, they had had it drummed into them by their bosses and suppliers that, if they sold Pepsi and you asked generically for Coke, they would need to confirm that it was indeed Pepsi and was that OK. I would ask for “A Diet Coke, please; or Diet Pepsi, or Pepsi Max or whatever you have – basically any diet cola, please!” That did usually get the message across.
Like I said, it’s a shame that you have to assume the worst when there are plenty of perfectly capable bar staff and cafe workers, but it gets beyond a joke in the end, the sheer number who don’t bother to listen. I don’t think that they’re actively thinking that they’ll ruin your day or irk you by deliberately giving you the wrong order; the problem is that so many simply don’t think at all.
People suggesting that you shouldn't order any kind of coffee/pop/milk/cake or whatever are clearly misunderstanding the basic idea of a café – it’s a place which displays a menu showing the options that they offer and you choose from those options – and you should be confident that you will be served the option(s) which you've ordered. On that principle, a 14yo should never go into a corner shop for a milkshake or a bag of crisps on the basis that the establishment also sells cigarettes and alcohol.