To turn down a load on the second half of a swap because someone else got more miles out of it than you is just silly. Either what you were offered is profitable, or it's not. How many miles the first leg driver got is quite irrelevant, since it has zero impact on your revenue. I've been in Detroit and received many load offers that were the second half of swaps going into Canada. I almost always turn those down simply because they are usually not profitable. If they were, I'd take them, and couldn't care less how many miles the other driver got. After all, I wasn't sitting where he was when he got the load, so why should I care? It's not like they dispatched around me to give him more miles so I could get less.
There are a lot of people who aren't allowed to go to Canada but are allowed to go to Texas. Should they not be allowed to pick up loads in Texas just because the consignee is in Canada? Dispatch would much rather swap out a load going into Canada way, way, way before it gets to Romulus. They have a much harder time swapping out loads in Romulus, simply because there are so few miles from that point on that it's usually not profitable for whoever takes it the rest of the way, and most people turn 'em down. If there is no one along route who can take the load and can also go to Canada, they have little choice but to swap it out at the border. That's why they now have drivers who do nothing but take loads at the border on into Canada.
For me to take the second half of a swap into Canada, the swap will usually have to be outside of Michigan or Ohio. Generally, Chicago, Indianapolis, Cincinnati, Pittsburgh, Syracuse... anything closer and there's not enough loaded miles to be worth it. I want about 250 under my belt before I arrive at the border. How many miles the first leg got, I don't care. Could be 200, could be 2000, all I care about is what it takes to get me into Canada.
But I hear that all the time, where "the other driver drove the meat and potatoes out of the load, and I get the scraps!" Well, you shoulda been sitting where the other driver was then. If you don't want scraps, don't sit next to the scrap barrel. Duh.