A £14 bad day
You can waste an awful lot of money in a single day if you don't plan ahead. This happened to me when I came back from holidays, and couldn't be bothered to prepare for the week ahead.
£4 on breakfast. I popped into the local convenience store and grabbed a cup of coffee and a cornish pasty. A small bottle of water would have cost me another £1
£3.50 on lunch. Nothing lavish, just went to the supermarket and bought a meal deal of a sandwich, pack of crisps and a drink.
£6.50 on dinner. After a long day, I decided to grab a takeaway before I went shopping for the week. I couldnt justify £10 on a pizza, so I went to the chippie and had a chicken pie with chips and a can of pop.
Not an overly extravagant day, butI'd actually spent £14. If I'd have been a little more extravagant, I could have easily spent £20 - £25 in a single day.
Like you, I'm no saint, and these days happen, whether I plan ahead or not. It's just a shock at how you can wast the equivalent of a whole weeks food shopping in a single day.
Your Dad would start a lecture now ...