English is a decent enough vulgar tongue to get by as a de facto lingua franca most of the time. Unfortunately, it also happens to be rife with pernicious abbreviation, some customary, some intentional, and some hewn from the topsy-turvy timber of accidental conquest.
"Love" is one such unfortunate casualty of the yaw of history.
You see, language helps define perception. Let me give you an example from one of the other languages I speak (poorly). In the Lithuanian tongue, the word ranka means both "hand" and "arm". And the distinction isn't merely a trifle of language. Lithuanians consider the hand (not to include the fingers) to be part of the same object as what we call the arm. It's one thing traveling from shoulder to knuckle. Sure, there are closer descriptive terms to distinguish the carpal area from the ulnar and radial, but like in English, they're specialist, almost medical terms. The Lithuanian vulgate is as I have described it. Similarly, there are different words, not merely adjectives, to distinguish between blue (mėlynas) and light blue (žydras). Yes yes, we have "azure" and "cerulean" and all those crayon colors, but for most folks, blue is blue, and they're just shades of the same color. To a Lithuanian, they're different colors entirely!
And so pity poor English and its lone, lonely "love". Contrast this barren catch-all with the four dazzling flavors from the Greek: φιλία (friend-love), στοργη (family-love), έρως (erotic love), and αγάπη (divine love). The language builds mental artifacts in the minds of the speakers, so you might forgive English-speaking people from confusing eros with storge, or the love of boning with the love of the hearth.
Marina Adshade applies economic reasoning to topics of love, sex, and sorting behavior. When we here at EE plug for legalized prostitution, I think we default to thinking of market-transacting love as purely erotic. When Adshade analyzes pairwise mating, she carefully distinguishes the long-term, barter-driven marriage market from the short-term spot transactions of the sex market. Speakers of Greek understand the difference much more clearly and naturally than speakers of English (on average, of course).
So with the four flavors of classical love, we might want to revisit what euvoluntary exchange looks like in each one. The lowest forms seem to be purely reciprocal in nature. A friendship is freely exchanged and faces low exit costs. Philia (and yes, this is where the whole "City of Brotherly Love" is from) must be euvoluntary, or else it becomes something else. Even mafioso who express familial love towards each other are not to be blamed for their affections, but for their coercion elsewhere. At the other extreme, agape is not really an exchange at all: it flows from the divine to the breast of mankind. Talk about a BATNA disparity!
So trade in the beast with two backs is something else, something apart, something distinct when we employ cautious linguistic partitions? Group X thinks so.