A lot of Krav Maga that is being taught in many places is bogus, ill-trained garbage in my opinion. The worst kind of training is false training, where you have just enough confidence to stick around, not enough skill to avoid a hospital visit.
If you goal is purely to avoid getting jumped or beaten up, then learning grappling techniques will not help you. Either go all the way with the training or keep it very basic.
I learned what I know from spending a lot of time on military bases, but my father gave me the best advice:
"Son, remember: no one wants to mess with a crazy person.....doesn't matter how small or he is or how old. No one wants to fight that guy that will gouge your eyes out or try to bite your fingers off."
One of the few times self-defense ever came into play was when I was a bartender, right before I went to school for a season. A guy got all tough at the end of the night with his buddies around, pretty much hinted him and 4 other guys were about to jump the bar....then my dad's advice came to mind.
I said something like this, mixed with a lot of F-bombs, "Please jump over this bar. They know me pretty well in the jail here and I want to bite one of your f-ing noses off. PLEASE COME OVER!" I had my eyes wide as they could get, started jumping up and down like a rapid monkey, punching myself in the head, repeating "Let me kill one of you MF's! WHOO!!!!"
They got the hell out of there, plus I attracted the attention of every person/bouncer in the bar.
See, this kind of thing doesn't get taught at Karate class
"They now look to a single and splendid government of an aristocracy, founded on banking institutions, and moneyed incorporations under the guise and cloak of their favored branches of manufactures, commerce and navigation, riding and ruling over the plundered ploughman and beggared yeomanry." - Thomas Jefferson, 1826