This is a very interesting question.
I seem to have different friends than yours - mine love to score well, but many also have a bad case of "tee ego"; that is, to them, it's not golf unless it's from the tips. Very few of them belong anywhere near said back tees also, and they end up with scores not up to their expectations, frustrated and wondering why. But dammit, they played the "men's" tees, they say!
In my experience there do seem to be many more players who do this than move up to shorter tees in the interest of lower scores. Believe me, I'll take your friends, thank you very much! They're not hurting anyone, they go faster, and end up happier.
In any case, to give my take on your question, golf for me is all about bliss. That can come from a great score, sure, but I've played long enough not to expect that and to get enjoyment from many other places. Thus unless it's competition (which is an entirely different game), I am the absolute anti-tee egotist, happy to play the purple challenger tees if that's what my playing partners want to do. I understand trying to see all of the architects intent, that is, "see the whole course", but I also know that tends to lead to frustration on all too many courses, as I hit long iron and fairway wood after long iron and fairway wood into greens, miss most of them, spend the whole day grinding out the short game, etc... For me there's much more bliss to be found in just playing wherever the others want and not beating oneself up.
I get crap all the time from my friends re this, as sadly I am the best player by far (I'm a humble 3-6 depending on the putts, and the best of them is a shaky 12). They can't believe I DON'T want to always play the tips and even try to get them to move up.... Then in my local club, even the low cappers there can't believe when I suggest we play "up".. I guess I am a strange cat after all. My basic take is I get beat up enough in competitive play - for casual rounds, what's the point?
A separate question occurs when playing a great course for the first and maybe only time. In those case, I can absolutely understand wanting to play the tips, to see the architects' intent, etc. We did such my one round at Shinnecock and though it thoroughly kicked my ass, I was ecstatic having it kicked... Somehow that seems to be the reason Shinnecock is there, to administer an ass-kicking, and I wanted the full measure. That occurs at famous courses all the time for me... But then if we have repeat rounds, move me on up, thank you very much. Perfect example was Sand Hills - I believe we did two rounds back, two rounds up, and that to me seemed perfect. "Saw" the course, got beat up, moved up, found it more playable - thus full enjoyment.
I ought to add one caveat - I will nearly never play forward tees while players I know are equal or lesser to me in skill play back. Thus I guess I do have some tee ego... for some reason the macho/competitive juices do fly in that rare instance and I move back! If I'm with people obviously better, than fire away, I don't care, I'll move up.
Maybe this makes no sense...
TH