Here's the difference between a Scrub and a Casual.
A Casual will look at an advanced technique and say, "Wow, hey that's pretty cool. How'd you do that?"
A Scrub will see the same AT and say, "ZOMG CHEAP you hacker you cheat I hate you!"
A Casual will lose to his opponent and say, "LOL that was a fun match. Wanna go again?"
A Scrub will lose to the same opponent and say, "ZOMG CHEAP you hacker you cheat I hate you!"
A Casual will hear about tactics and strategies and say, "Well that sounds cool, but I'm just don't take the game that seriously. But I'll tell you anything you wanna know about <insert unrelated subject here>."
A Scrub will hear about those same tactics ans strategies and say, "ZOMG CHEAP you hacker you cheat I hate you!"
Casuals are actually pretty nice, you see.
On the other hand, scrubs tend to annoy you to such a point that you wanna be cheap, hack the game, and cheat like crazy JUST to make them hate you.
That's the difference.