gun transfer question

:/ I was reading that straw purchases help criminals to evade background checks or help illegible residents to acquire the firearms. (This implies that background checks are unnecessary in private transfer? why not?)

I also don't understand why is it that CA residents can't buy certain guns, but can own them under legal private transfer--pardon my ignorance, but why is the prohibition there in the first place if they can still be owned at the end?

So far as I understand it, which is very little, I feel that the laws can be very prone to corruptions--If it is illegal to buy for a friend, then can't one just give it as a "gift", and then later his friend can simply give him money or other items as a "birthday or Christmas gift"? After all, friends sometimes give to one another and perform deeds to help one another out for free. I believe we might not explicitly say it, but subconsciously we do keep a mental tab on how often and how much people have helped us, and we tend to reciprocate and to thank them in return. And how can the law enforcement check on this--if someone says he is giving the gun as a gift, but privately he is receiving a "compensation" while he denies that the compensation is related to the gun purchase? In another words, let's say my friend trusts his friend enough that he took up the trouble to go to Nevada to buy this gun as a sincere birthday gift because his friend is so passionate about the gun. Then, out of gratitude, unplanned, his friend reciprocates by giving him help any time he wanted in schoolwork (or anything). To me, this is a gun purchased for compensation, or this can be also a sincere gift... @.@ (How does one differentiate a gift from a transaction w/compensation? If a gift is defined as giving an item without compensation, then if I smile at someone, the positive moment that the individual experiences then may be compensation enough for me. One may argue that such a compensation has no money involved, but these experiences also have so much values that I'm sure some people may be willing to pay money to get them if they can. If someone can explain to me the reasons behind the current laws, why they are necessary, how they are efficient, and the implications within them, as well as comments on my thoughts, I'd much appreciate it.)

Or, in order to make it "legal", can't my friend just have a change in mental attitude?-- that maybe he would like to try the gun out himself, but he acknowledges that if he doesn't like it, there is also an option of selling it or giving it away as well. Having no experience in gun dealings and in laws, I don't understand the reasons behind the laws. I know that there are mountains of information & debates regarding gun laws and ownership in America, but I am getting a little overwhelmed by the forums, discussions and laws that I've found. If not for my friend, I myself would not have ventured into this heated topic at all. Thank you for all the comments, thoughts and advice. I can now tell my friend now some basic info and refer him to sources where he can then make an informed decision himself. :)

/r/Firearms Thread