ohhhhh...well, you'll find out what Join Avenue is when you reach Nimbasa.
If you need anything to be convinced that it's helpful, some items give your Pokemon 64 EVs in a stat and can raise their level by up to 8.
Go on the GTS.
Put up a Magnemite and request a Magnemite in return.
Repeat.
And again.
And again.
and again and again and again and again
People will flock to your Join Avenue just like mods when they change their avatars
"I'd run recover, but Porygon isn't exactly the fastest of the bunch. In fact, he'd probably go 3rd in a battle, but I'll run that for some battles and see how it goes, thanks!"