Is the American wedding system an in-direct dowry?

Cultures often differ on whether they have a bride price or a dowry system for contracting marriages. In cultures where wives pay their own way, such as in New Guinea and African hoe agriculture economies, where much of the farm work consists of light weeding in light soil, it's common for grooms to pay their brides' families for their new wife's future services, often in cows or other valuables (Borat says that in his country, a wife costs "15 gallons of insecticide").

In cultures where men do much of the farm work (e.g., heavy plowing in rich soil), however, it was common for the bride's parents to pay a dowry to the groom. 

Now, anthropology is full of exceptions (what Robin Fox calls "ethnographic dazzle"), but this is something of a general pattern.

In normal American culture, we don't have either, at least not explicitly. And yet, my wife contends that the standard wedding protocol provides an in-direct dowry from the bride's parents laundered through the guests. 

I am the last person to pose as an expert on etiquette, so I may be getting this wrong, but her parents shelled out for a big wedding and big reception. My parents paid for the smaller rehearsal dinner the night before (largely attended by my relatives and friends from out of town) and, perhaps, the alcohol at the reception (I can't remember). But my brides' parents bore the bulk of the costs.

At the reception, lots and lots of people came up to us and handed us money. Others bought presents (some of which we returned for cash -- I especially recall six small plain water glasses that I was about to give away until I turned them over and saw "Baccarat" stamped on the bottom -- we returned them for $350, which was nice money in 1987). 

The general idea is that guests should give the couple cash or a gift roughly equivalent to their share of the cost of the reception provided by the bride's parents. In other words, the gifts functioned more or less as a dowry from my in-laws to set us up, but indirectly routed through the guests.

Does this interpretation make sense?