Why Jacob apparently travels to Mesopotamia without a brideprice is something of a mystery; my guess is simply an educated one. One movie portrays Jacob getting robbed (by an ally of Esau); that, too, is just a guess, but at least it recognizes the problem.
The promise of land and descendants had cost Abraham many acts of faith over the years; he wanted to ensure its continuance to the next generation. To forestall the danger of Isaac settling back in Mesopotamia, Abraham sent his servant rather than Isaac there, and warned his servant not to take Isaac back there (24:2, 6-8). He also gave a huge brideprice (24:10), making the acquiescence of the bride’s family quite likely (24:30, 35). Even if the prospective bride would not come, however, the servant should not take Isaac back there (24:8); God could provide a wife for Isaac by another means.
By contrast, Rebekah and Isaac send the blessed heir Jacob to Mesopotamia, and he apparently carries no brideprice (29:18). Perhaps earlier conflicts with the Philistines had reduced Isaac’s wealth; perhaps he does not share his father’s deep passion; perhaps he simply trusts that God will take care of it, since Isaac believes the efficacy of his blessings (28:3-4); or perhaps a combination of these factors influenced the lack of substantive bride price.
Whatever the reason, though Isaac clearly does want Jacob to get a wife from Paddan-aram (26:35; 28:6-8), he does not send him with a substantive brideprice. But my best guess is that Isaac is still upset about Jacob’s deception. Jacob has the blessing, and Isaac reaffirms this (28:3-4), as Genesis gladly reports. But Genesis leaves unsaid why Jacob is not equipped with wealth. Esau will continue to build on Isaac’s present prosperity (33:9); Jacob, who cheated to get the eventual inheritance, will have to make his own way for now. By the end of Genesis, however, it will be obvious that God’s blessing pronounced by Isaac is worth far more to Jacob than anything else Isaac could have given him.