That could go both ways, maybe they didnt own a plantation or have use for a slave. But they still could support it. Or, they could be completely against it, and think its completely wrong and dehumanizing, they could help runaway slaves get to the north.
Explanation:
mercantilism, economic theory and practice common in Europe from the 16th to the 18th century that promoted governmental regulation of a nation's economy for the purpose of augmenting state power at the expense of rival national powers. It was the economic counterpart of political absolutism.