There're many reasons, but for me, it's easier to track and find my favorite opponents in live games, if they are in your friends list you got notified of their divine presence, etc.. :D
Why do you send friend requests?
If it's your favorite opponent maybe you do have your reason but i'm nobody and also Russian. Find someone else to follow.
Oh yeah I got it, you're a nobody and Russian and don't know how to play chess... Jesus fuckin Christ, now I have to find someone else to follow... :D
Hahahahha, "I'm Russian " hahaha hahaha hahaha dude what
Some people refuse to play with me because of that so figure. Russians are negros for the rest world.
Suman3
I'm glad that you've got the idea.
Low rated players when they see high rated , for example everytime i type anything in chat on top game at that moment at live chess, i almost every time receive friend request from a around 1000-1300 rated player... probably holping i can play couple games with him.
No joke. When i play friendly unrated games vs low rated (when i am little drunk for fun or practice openings) they half the time after games reply gg thank you for playing me or last time i think for 2nd time one cool guy sended friend request, becouse i played him 5 games or something saying you are really strong player (no sarcsm) and i was what, i just move quickly. I played really bad actually, trash opening and stuff.. really bad.. but in their eyes we are Masters for them : ) But most of the time i decline all "friend" request. No point spaming my list with "real friends"
Maybe in near future will offer some bullet/blitz lessons for those guys for couple bucks.
bestpony
It would be nice and an option to disable chat permanently. I'm here to play chess not socialize. Why do I need bunch of "friends" who never send me any message? Ridiculous.
AIM
I can understand why people send you requests. You are good at chess but i'm a crap. Recently a girl from the UK has sent me a request after beating me(I had material advantage but lost on time as usual). Of course I declined her request, creepy people.
I am still a junk man. I just have some intuition with bold sacrifices with good mouse skills at time trouble. But i earn this by hard work, watching and spending tons of time on chess. Today i lost 200 blitz elo points back to 1700, but players i played were really strong 1800-2000 OTB. I hate when i am playing strong players but with low rating. Underrated agressive players are the worst. How can you be 1750-1850 when you are maxed few weeks ago at 2100~.. It just sucks.
But hey if you feel she is really a girl chat to her.
If you can collect beautiful women (avatars) as friends, it is undenialble proof that you are a handsome virile stud.

how else to explain it?
Why do you do it? I don't see any purpose of it. People please, stop doing it, it's annoying. Especially because i am Russian.