I think it really depends on elo, and how fun you make the game for your allies.
In your Vayne + Lulu example, if the Lulu stays bot the whole game and gets the Vayne fed and spends the whole game only supporting Vayne, then it's likely that everyone else will honor Vayne, and Vayne will honor Lulu. Why would mid/top/jg honor Lulu when she didn't do anything for them directly? Whereas Vayne killed targets that would have killed them, and Vayne took towers quickly, etc...
In contrast, if Lulu roamed mid a few times during lane phase and also got the mid laner a bit of a lead, and maybe responded quickly to an invade - then mid and Jungle would honor Lulu instead of Vayne. They both see Lulu actively helping them enjoy their game more, and it's those moments that they'll remember on the end screen.
Of course, some people will always honor the person who carried, or even the person that just did well on the last teamfight. I remember a game where I was playing Ahri mid and had a particularly bad Yasuo top lane. He fed lane pretty hard, and both ADC and jungle were being pretty toxic because he was so far behind (well, ADC slightly toxic, jungle extremely toxic). I was keeping quiet and focusing on carrying the game, while not as fed as their top laner I had a pretty significant lead and single handedly kept the game alive from 15min to probably 35min before some of my allies became relevant.
Then late game, Yasuo hit a 5 man Tornado, we got a clean ace, and won the game. Immediately after the fight our Jungler says in all chat for everyone to honor Yasuo he single handedly won the game.
And I'm sitting there thinking wtf... the same guy you've been harassing all game long for hard-feeding his lane opponent, you're now telling everyone to honor because he made one good play.
Of course at the end of the game, I honored support, I got one honor from Yasuo, and the other 3 honored Yasuo so he got the icon thingy pop up. Seems like the first 99% of the game doesn't matter, if you make a play in the game-ending fight you'll get the honors.
Finally - at high-ish elo (at least in Plat), people seem to honor the support/tank a lot more often than other roles if nothing exceptional happens. I do it myself admittedly. If a game was a reasonably close game, no one was toxic, no one stood out, then I get to the honor screen and see 4 champions and just think "IDK they were all alright"; I'll generally pick the support or tank (to "thank" them for playing a less desirable but very important role on our team). And 9 times out of 10, that player will get the 3 honors icon. Same thing goes when I feel like I've hard-carried and expect everyone will honor me - the support will get the icon. Even if I'm 12/2/14 in a game that we win 28 kills to 24. And I never say anything, nor do most players that end up getting the honor.