First of all, there is nothing illegal or immoral about taking a Carribbean or foreign grad.
OK great, tax dollars pay for spots. And? They're still probably just as likely as a US grad to stay practicing here in the US. If they stay in USA, I don't see how taxes are a valid point. If you want to take it to a state level: should programs be allowed to match out of state residents? Should medical schools be allowed to take out of state students? After all, those students/residents are more likely to leave the state after training.
Also, how much in taxes have YOU (not your parents) paid compared to the FMG? For most who went straight through school, the answer is probably not much. Plus, if you went to a state funded medical school, you probably already USED more tax money than you've paid in...and more than the FMG.
Who knows if this person had connections. If they did, that's great for them. I had connections too -- from hard work, research, and networking. I know there were people in my class with better board scores and more honors than me who failed to match into derm. They had the numbers but got lost in the background of the game.
Another point: I didn't have any parental connections, but those who have them still don't have a cake walk. Having a parent dermatologist/doc MIGHT help a little, but not as much as you'd think. We get calls every year from parents (dermatologists, chairmen of other departments, deans of schools, politicians, etc) requesting (and sometimes demanding) we interview their child. As far as I can tell, it's never helped any of those applicants. If anything, it hurt their chances. In other words... connections from people who have nothing to gain by saying nice things about you mean a lot more... so make some!
Overall, a "better" candidate depends what the program is looking for. If you can make a fit into a program academically and socially, the match will be your friend. If you can't, you'll just be angry that others went out and made connections while you memorized the first aid series.
I guess all I have to say to FMG/Caribbean grads who match into derm: CONGRATULATIONS! Don't let jealousy on these message boards taint what you've worked hard for.... Good luck, doctor