Loving the helpful little note from mum still left on!!
I think part of the problem is that recruiters are very different, and you usually have no idea what sort of person they will be. One will say "I don't care about your interests and what you get up to at weekends" but another will say "I like a conversation starter and to be able to see the whole person rather than just cold, hard facts". Some will find the inclusion of a photo weird and unnecessary whereas others will find it helpful and friendlier to be able to put a face to a name in their heads as they look through their history.
As has been said, you might consider your GCSEs and A-Levels (or equivalent) completely pointless when they were 30 years ago, but some employers are very insistent on basic maths and English skills - and there's nothing else after that stage in your life that objectively confirms whether you have these skills or not. They may also be of the opinion that they are the foundation of your abilities and, if you didn't even do well with them, you could just have been winging the rest ever since!
Whilst it is genuinely funny to hear the stories of people writing it on bog roll or sending in 20 photos of them with their nan at their graduation, it's easy to forget that constructing a CV for the first time is a daunting prospect - and that many people will have grown up in less-than supportive households, underprivileged backgrounds, patchy education history etc. It's the accepted norm for many of us, but if you're told you have to send one in when you just need to get work in a very basic non-skilled NMW role to earn money to pay your bills, it must often seem like a great big meaningless mountain that somebody has put in your way, just to show you up.
I've got good qualifications and am reasonably intelligent, but I would struggle with the ones who insist on a full handwritten A4 cover letter (even though the role is 100% computer based), as I have severe nerve damage in my hands that makes writing more than a few words by hand very painful indeed. My choices would be to be in a lot of pain for hours whilst I completed it, not to apply for the job on that basis alone or to just send it in typed with a brief explanation. Even in the case of the latter, some employers would see it and be more than happy with the alternative when an applicant has a disability; but others - especially the sort who insist on seeing your handwriting in the first place when you'll never be using it in the job anyway - will write you off as lazy, arrogant and/or unable/unwilling to follow basic instructions and orders, or they may simply feel glad to have 'dodged the bullet' of having the 'burden' of a disabled person in their team (in which case, I'd never want to work for somebody like that, even if I personally enjoyed perfect health).
For a number of reasons, it's very possible for a CV to actually present a barrier between a very suitable employee and the right job rather than helping with the honing and filtering process to make sure that everybody is in the right place for them and their employers.