The reality is that its not considered "normal" to most people to casually hang out with friends, girls or guys, naked. Im not passing judgement either way, but its just not typically acceptable. Im gay and I very much appreciate nice male equipment, but to be honest, I have no desire to see random friends nude. Its just not something that concerns me...I mean, why does it matter if your non-sexual friend looks good nude...its irrelevant. In college I had a few straight friends, some of them very attractive, who liked to watch porn and JO together sometimes. While I thought this was hot as hell, it really did cause unnecessary tension in my friendship with them, as I tended to spend a lot of time wondering "what if I just asked them if I could give them head instead...that would be so hot...I wonder if he'd go for it..." The overall outcome was that it was just unnecessary tension. Also, for the unattractive ones, I just didnt want to see them at-all...it was almost offensive.
Again, this is coming from a farily open-minded person. Ive had a few non-sexual friends, straight and gay, that Ive masturbated with on-occasion, and that was fine at the time (drunk and horny.) But, there was an explicit point to it. Before and afterwards, we didnt just hang out naked though. I even had one bisexual friend who would randomly ask if he could see my dick because he was infatuated with size, and it actually made me not hang out with him as much because of it.
In summary, whatever you want to do in your house is fine, and if your friends are fine with it, then OK, but I dont think you could fault anyone in any way for being uncomfortable about it, even to the point of not hanging out with you because of it. I wouldnt hang out with friends who acted like that regularly.
Plus, I personally think guys are hotter in sagging or low-cut jeans with a cool-looking bulge and nice ass, than actually nude...it leaves more to the imagination. And I will admit I have some straight friends that I admire in this way quite a bit. But, I dont have much desire to get naked with them, because I know its pointless.