<more seriousness>
I think that the problem is that these confused people don’t have a very definite conception of what “love” is (for clarity’s sake, let this include any and all vague distinctions), yet also have this vague idea that whatever it is must only exist in the context of marriage. So they develop the belief that the developed and committed love based on lots of trust, respect, and yes, giving, etc. that exists in the context of marriage is the only form in which “real love” can exist.
My opinion on the matter: Love is just a raw emotion that can be channeled negatively in the form of superficial lust or emotionally unhealthy relationships, or positively in committed, healthy relationships (i.e. marriage), but generally begins in a more or less neutral capacity (which I would call chemistry, I guess). Also, marriage won’t magically make the “real love” (here I mean positive love) happen – it just sets up the framework in which it is most ideal for “real love” to develop. Likewise, chemistry before the marriage won’t necessarily make the “real love” automatically happen.
So really there isn’t any point in arguing either way, because it’s not like there is a magic formula that everyone must follow to make it work.
just my thoughts