I hate the wording of it, but it's because it's a legal requirement, since becoming part of "challenge 25", that the colleague assessing your age has made the assumption that you are "CLEARLY over 25", they are literally logging in and electronically signing, to say that they deem you over that age. If it simply said "no i.d required" and the customer was in fact 23/24, it could cause issues with confusion over the wording, the colleague needs to actually see that wording in front of them, incase it was found that the customer fell into the "test purchase" category, which Tesco need to pass to keep their store alcohol licence. Tesco regularly get test purchasers in, who are paid to attempt to buy restricted items between the ages of 18-24, and if they do not i.d them, they would get in huge amounts of trouble. So the wording is purely a reminder and prompt to the staff to ensure they carry out their age assesment prior to authorising the sale. Also, if an employee sold alcohol to someone under the age of 18, Tesco would get a substantial fine, the colleague would also get a fine, and lose their job, and the store would potentially lose their alcohol licence, which is why the challenge 25 was brought in, to prevent underage sales ever happening. It has to be very strict, and the colleagues don't enjoy i.d-ing people who are clearly over 18, but have to i.d anyone who isn't clearly over 25, or risk their job, a fine, and the stores licence and reputation. What I hate, is the customers who moan and grumble, and sometimes get aggressive and abusive towards staff when they get asked for i.d and don't have it on them. "I'M 22/23/24 FOR FUCKS SAKE" is a common one, and I tell my staff to answer politely with, "I'm glad I asked you for i.d then, as it shows I'm assessing your age correctly, and I need to see it if you're under 25."