I write reference letters all the time. For very important ones, I have a highly respected English teacher give them a glance for any errors, or to make sure everything sounds good to someone reading it for the first time. And, as a matter of fact, we were chatting about letters of recommendation before a dinner that we held for our top students. (The two of us, plus a handful of others organize a nice dinner, and the top two students in every course in high school, from 9th grade algebra, up through our for-college-credit courses taught as adjunct professors, get monetary prizes.) She remarked that I wrote some of the best letters of recommendation.
I can assure you that in many situations, those letters are read. I've received feedback from a couple major universities on those letters. Last year, I wrote letters of recommendation for college acceptance or for scholarships, for about a dozen students. I was at some sort of major honors dinner, about a half hour away from here, where some of my former students received scholarships. They received the largest scholarships available. Excerpts from the letters of recommendation that I wrote were read when they introduced those students. I'd guess that last year, my letters helped students net $100k or more in extra scholarship money. If even 10% of that came down to my letters, I'd say that it was time well spent. Every student that I wrote a letter of recommendation for college acceptance, got into the university of their choice.
I don't write letters for everyone. For some former students, I have put multiple hours into crafting the finest letter I possibly could - no lies; no exaggerations; just put forth the student as positively as I possibly could and make sure the letter was very personalized.
Today in one of my classes that's a mix of juniors and seniors, every senior was absent. Our school's version of "senior skip day." Though, they provide a TON of safe & fun activities for the students. But, just as I closed the attendance on the computer, a lone senior wandered into my classroom. She's on a scholastic team that's made it to the state finals & will be missing class the rest of this week, so she thought she had best come in, so she didn't miss so much review for the final exam.
When she returns on Monday, she's going to have an unsolicited character reference from me/generic, though personalized, letter of recommendation. A lot of other seniors could have really used the extra review time today, but she was the only one who showed such character that she were willing to sacrificed 45 minutes of fun to ensure success on her final exam. I guarantee I can turn that into a very well written paragraph in a letter of recommendation.
Now, if she had even once exhibited the attitude of the OP in my classroom, I wouldn't have ever bothered.