Think there are generally two camps in this debate, as demonstrated herein, which I think really depends on a man's inherent personality, opposed to the female species as a whole, per se... men who will never be just friends with a female, and those who can.
Personally, I'm in the latter. I grew up in my formative years primarily with my mother, grandmother and five female cousins, until my father adopted me and my brother and male cousins came along. These early experiences obviously have an influence on us later as adults.
Two points of clarification as is TMKs usual way.
1) I wouldn't say I'm particularly close to my female friends, not in the way I am with male friends. But still, they have their place. I also cannot be friends with particularly girly girls - weirdly though, these are they who I am sexually attracted to in general terms.
2) I don't keep friends with women who I am interested in sexually. Rather, most of those I keep are clearly interested in being more than friends, to varying degrees. I also don't tend to spend extended amounts of time in the company of females, other than at work.
but they provide no special benefit (sex)
This is too simple a philosophy. Sure, they may not be direct sexual options themselves, but what they do bring, among other things already mentioned, are
other females as other sexual options. In fact I'd say the number of options I've been granted indirectly from female acquaintances outweigh those gained from male acquaintances is probably by about 9-1; no exaggeration.
Example; I just moved in with two females. We don't tend to socialise together much, but they are organising a Christmas Pub Crawl next month, to which in attendance there will be
at least half a dozen girls I've not met before.
Example; previous girls I've known introduce me to their friends, sisters, cousins blablabla. I even had an 18month relationship with the sister of one female friend.
I can honestly say it doesn't happen to this extent with male friends.
Long story short, if you don't have female friends, you should try it.