Purple hearts aren't awarded favoring what branch of service or particular role you played in combat.
Doubtful - otherwise thousands of men could have used the "Kerry method", and claimed medals for little scratches. Kerry was a shrewd blueblood who was looking ahead to a political career even back in vietnam, and was trying to inflate his "record" by demanding medals for things that it would never occur to normal soldiers to - they'd probably be ashamed to when other men were getting them for losing limbs.
When you can't debate the facts (STILL waiting to hear from you about the famous Kerry Cambodia Invasion that never happened ) put up straw men.
If dole got an award he didn't deserve, that doesn't mean Kerry deserved one he didn't deserve. Again, crack a logic book and start reading on page one.
The Purple Heart is awarded based on a certain set of criteria. If those criteria are met, a Purple Heart will be awarded, regardless of the severity of the wound sustained.
Point being, you don't have to lose a limb to get the Purple Heart.