It's not that simple. An Indian expatriate's remittance may leave American shores, for example, but then re-enters when their family buys iPhones, Ford's and Hershey's.
The problem is that most American exports are luxury goods (even in agriculture) and when you come from a poor country where a few hundred dollars makes a huge difference, those exports will account for a tiny amount of the capital sent there. There are many long tail benefits but I doubt they are quantifiable enough to say that the drain from remittances is anywhere near break even.
Edited to add: my family doesn't even need the money, despite having health conditions that would economically cripple someone in the US without the best insurance. Salary + pensions + free education and healthcare are enough to survive so most of the money I send them are to give them breathing room and spending money. I think half of what I send them gets spent on spoiling the younger family members and the rest goes into a rainy day account. The only time they "spend" on American products is when one of us in the US buys them iPads/iPhones (on top of the remittance) as gifts on one of our visits and they buy a $5 game twice a year for the kids to play.
That said, if Americans knew how much of the >$100 billion remittance market went to buying little kids books, candy bars, sports equipment, and board games, they'd think the money was worth all the happiness it brings.