Same with a costume. In a nutshell, Tolkien Elves appear to act (and think and feel and literally BE) the same as Humans. How could this be possible? Well, because Tolkien's very Human mind imagined them.
I don't for a moment believe that players in TTRPGs are trying to examine what it would be like to actually be a person that has lived for hundreds or thousands of years. Would that even be possible as all experience is limited by our Human nature? My opinion is no. If it were, then the greatest works ever written wouldn't always be limited to those experienced by Humans.
I do believe that players in TTRPGs want mechanical statistics to differentiate their PCs from other PCs. For some reason D&D especially has become focused on this aspect in recent editions by allowing a plethora of, I hate to say it, Humans With Funny Hats! Sure the dragonperson is cool looking and you made up some goofy nonsense culture for it, but how come it acts (and thinks and feels) the way a Human would. Oh yeah! Cause it's mind is a Human mind.
Plus, considering the content of some recent discussions regarding D&D and the various Humanoid races in the game and how they reflect upon the game, maybe it would be best to eliminate all Humanoids that aren't Human from the game. Nuff Said!!!
As a side note, I personally have found that only allowing Human PCs and reducing the reliance on mechanics to differentiate PCs is a very good thing for the roleplaying aspects of the game. For some reason players seem to work just a little bit harder at differentiating their characters through action when they don't have mechanical statistics to differentiate them.
Anywho, sorry for the huge rant. Hopefully it helped clarify my position, and dislike of, Non-Human PCs.
I must restate, "acting the same as Humans" is the wrong way to say it. Humans and Elves act like People. You're approaching fantasy with "only human=people." A "Human Mind" doesn't mean anything if something like it can be replicated by non humans, in fantasy and in real life. Your argument is based on a false connection, and I've addressed "Humans with funny hats" as a term here.
I don't believe that you're responding to my points, now. Exposure to the idea of the results of being another species is what I've been talking about, not some ideal character study.
I don't agree with whoever said eliminating a vital part of the game and community would be a good idea. If forcing everyone to play the same thing forces them to express themselves in other ways... yeah, obviously! This problem can be fixed by further RP encouragement. It's like observing that students in school uniforms, if they can't dress normally, will try to individualize their uniforms in small ways. Fine details do show care, but it's not fun for players to be shoehorned into this. People play them, so it should be included, and alternate races are such a big part of Fantasy and even NPCs and such, so why take it away?
I'm going to make a less nuanced point. I think anyone who can't even see the appeal of other DnD play styles is the problem, not the alternate play styles. Character builders are fine. Alternate races are fine. Rules lawyers are fine. Even self-limited campaigns are fine, so long as you're not advocating for the whole game shifting into it to take other's fun or being blatantly closed minded. That's the beauty of TTRPGS, you give people all the tools for all of their options, and you cut it down from there to build your experience. It's great to have rules for stuff
if you wanted to use it, rather than forcing the whole DnD player base to individually
home-brew an entire system that WotC fills textbooks with.
I think I've adequately answered the initial prompt. People play the alternate races because it's fun for RP and mechanically, even though it's technically no more powerful or more "deep."