bsrizpac...it's obvious you are a McDojo graduate. Either you had no skills or you had a bad school. Either way, just because you obviously suck at fighting, doesn't mean everyone does. Put the blame where it belongs (on you) not on every karate school.
Double Dragon...there's more good karate fighters out there, than most think. I studied a very practical style, Sam Pai Kenpo. I sparred constantly and fought in every tournament I could find. That was back in the day when Karate tournaments were real, not like they are now.
You'll have to ask an Ed Parker guy about the Elvis thing. Mr. Parker was a martial arts genius and a tough guy. He didn't sell belts, my teacher earned his and it one of the best Kenpo guys in the world. People talk smack about Mr. Parker now that he is no longer with us.
"do Karatekas regularly spar with punches to the face? "
That's sort of like asking if dogs gave black fur. Some do, some don't. There's lots of karate schools allowing face contact with gloves etc. How do you think kickboxing started?
Magnus...if you have good kicks, you can keep the boxer from doing what he does best, which is boxing. There are many other reasons why it is more effective, like not being a sport oriented.
Da Swede...of course we spar with face punches and groin strikes. A punch may have less distance to travel, but a kick can be used where punches will not reach.
Da Swede...my little guys are fine. When you spar with groin strikes, you learn to protect your center line. I use 3 Shields, which has great blocking.
A knee or kick to the groin, followed by punches and elbows will take someone out. Boxers hit hard, but so do good Karate guys. I've been hit plenty of times.
"and yes a kick can be used to the groin and the knee but that doesnt mean it will end a fight, a punch to the jaw from a pro boxer will usually mean the fight is over and you will be picking up your teeth after you wake up"
No single strike is 100% gauranted to end a fight. How many boxing matches or MMA matches end withthe first punch landed. Typically, it's a war of attrition. You fuck up his leg, his footwork will suffer. Kick him in the nads enough, the round kick he tried when you jammed his nads might not me so attractive, or maybe he'll hesitate. That said, those are not totally easy to land well either, but no harder than landing a cross or whatever.
If it was a simple as 'Oh land a right cross and he'll go down' then why do boxers bother with phaggoty jabs, footwork, fakes, bobbing eaving and other stuff not right-cross related? Simple answer - because in boxing defense and ring smarts counts for more than the ability to throw a bomb at a heavy bag.
Also, if you square someone in the nuts, or sock them in the head, you'll possibly have a 5 - 10 head start for your 100 yard dash to the nearest subway/public place outside of the alley. So often times there is an option to end the conflict, if not the man. This is not an option in the ring.
"how many KOs in MMA/Striking are with kicks and how many with punches?"
I can't give you the stats, but I've seen Liddel win with both quite a few times. Or Silva vs Sak part II (soccer kicks), iirc. There was that Gracy "up kick" to Oleg that definitely turned the tide as well... And Cro Cop was making some easy money with his high kick (there's a karate guy for you (self trained to, no?), btw).
But this is a bit of a red herring, most MMA guys kick to the legs, and the farthest I've seen that go was Paul Varlens collapsing to the ground from to many leg kicks. The better MMA guy will have profficiency in more than one weapon. Only a 'stylist' would argue the merits of kicking vs punching. A realist takes what he can get.
And none of this has to do with kroddy per se.
IMO, the main thing boxing has over karate is the defense against punches. Except for overhands, you can find a similar movement in karate to most boxing punches - with very similar body mechanics. But the blocks take too long to pull off, if you stick to kata form, you have to move your arms twice as fast as the punching guy. Most karate guys will actually cheat a bit and modify their blocks, make them smaller, in actual sparring.
And boxing uses gloves, so in a situation with gloves, the defense style which uses the fact you have gloves is also advantagous.
As for kickboxing, it was invented by karateka in the US. That's where the kicks come from.
I work out with a guy who used to box for money in the old country (Russia). If we ever go hands strikes only, he wins, hands down. Let me use all my infighting skills like takedowns, joint locks and chokes, and it's a bit of a different story. So we teach each other and we get both get better overall.