Yest it is the case for any content ISP (that they send more than they receive), but that imbalance should be accounted for in the peering agreement contact between them and the consumer ISP (like Verizon). The contract allows certain transit levels to and from the parties. Either party is obligated to only support the receipt of the level specified -- no more. That's what we're seeing with the Netflix traffic coming to the Verizon consumer ISP network from NTT, L3, and Telia (to name three of which I am aware).
This problem is slowly going away. Users at east coast locations have reported that Netflix traffic now comes directly from Netflix without going through a third-party like NTT, etc. Dallas-Fort Worth uses this week reported the same direct routing. This is a result of the announcement awhile back that Netflix was going to connect directly to the Verizon network rather than routing through third parties. (For those who care this is not "Netflix Open Connect" but rather a direct Netflix connection. There is a big difference between the two.)