whats the big deal with picking scabs?!

Scabs are a way of your body healing itself, by picking it you are making it take longer to heal and could leave a scar.

I have no idea. I'm 58 years old know and since I can recall, I always, even to this day, picked off scabs. Our parents concerns about this activity is probably due to concerns about infection. Scaring will occur regardless depending on how deep the wound is, so that concern is irrelevant. However, the concerns of infection is not. Say for example, that you happen to have picked up a microscopic bacteria such as the flesh eating variety on your hands and then you pick of a scab on a wound. You've now infected yourself with a bacterium that is very dangerous and life changing. Regardless, while I did not know anything about this type of bacteria when I was young, and now I do, against my better judgment, I still pick off my scabs. My illogical reasoning: I believe the wound heals faster. Does it? Don't know and Don't care. It's habitual. ;)

It could leave scars that you don't want. Cover them.

You will get scars ..