Sorry that scenario doesn't fly:
Netflix has peerings with:
AS2828 XO-AS15 - XO Communications,US (Tier 1)
AS55095 AS-NFLXCORP - Netflix Inc,US
AS3257 TINET-BACKBONE Tinet SpA,DE (Tier 1)
AS4436 AS-GTT-4436 - nLayer Communications, Inc.,US
AS3356 LEVEL3 - Level 3 Communications, Inc.,US (Tier 1)
AS16397 ALOG SOLUCOES DE TECNOLOGIA EM INFORMATICA S.A.,BR
AS26592 ALOG SOLUCOES DE TECNOLOGIA EM INFORMATICA S.A.,BR (Tier 2 - Has large footprint in latin america).
AS1299 TELIANET TeliaSonera International Carrier,SE (Tier 2 - Apparently the largest fiber providers in Europe).
AS174 COGENT-174 - Cogent Communications,US (Tier 1)
So no this isn't a case of exclusive peering, Level 3 being such a large provider just happens to be the best connection between Verizon and Netflix.
Secondly, that whole thing of 'Level3 to Verizon: "Ok, that will be $X"' has no bearing on a peering agreement, the statement would have been more like "The link between us is congested, want to upgrade the link?" each side upgrades their switch (if neccesary) and they connect the cable / fiber (given that they are in the same location we are talking about a multimode fiber patch at the high end).