I do not understand these people, what is the logic of giving Merit to a person who has more and more)
Honestly, I don't get that either. Giving merits to Theymos or Satoshi is just like wasting them, even if the posts are fantastic. sMerits have a utility other than rewarding good posts (it allows people to rank up), and I think people either forget that or don't care.
I guess everybody has their own criteria for merit sending and, unless trying to obtain a benefit or trick the system, it is fair use. I, for once, have given my "obligued" merit to Satoshi, also because another reason for merits is to remark good posts no matter if the recipient "needs" the merits or not. That being said, I try harder to give merits to more "junior" members where I see potential than I do to Legendaries that don't really "need" it.
IIRC, I have only sent a single Merit to Satoshi, even if he would deserve way more. Not sure if I already sent any to Theymos or even Hal Finney, even if I am sure I would do if smerits weren't that scarce.
In other words, my requirements for a meritable post are harder when it comes to "well-fed" Legendary members but since most good (according to my very subjective and occasionally ridiculous criteria) posts usually come from them it is fair most merit go to them too.
I don't think giving credit where it is due is "wasting them" even if the recipients "don't really need it".