This is the second time in a short time that I've seen someone comment on a thread on the first page without having read the previous comments. Does this happen a lot?
Unfortunately, this is something that is a daily occurrence on the forum, because for some, reading other people's posts is obviously a waste of time. It's not just a problem in spam megathreads of 10+ pages, but also in threads of only 1 or 2 pages where you can see older members asking questions that were answered just a few posts above.
There are several options that we can do when we notice such behavior :
1. Report such a post to the moderator as repetitive content/signature spam - and hope that after the deleted post the user will realize that he did something wrong.
2. Publicly warn the user to read what others have written before him in the hope that he will accept the suggestion and be more appropriate in his posts in the future.
3. Report such a user to his campaign manager (if he is in a sig. campaign), although it should be remembered that each manager determines the rules when it comes to megathreads and to which page the post can be paid.
4. Put the user on ignore and pretend that nothing is happening, which is the easiest option, but for me personally, it is also the worst because then nothing will change for sure.