A lot of Netflix users say they might drop the service if it starts running ads. The streaming video service is testing ads that would promote its growing lineup of original content. A new study says many viewers are against the idea of running ads. The study by Hub Entertainment Research found that nearly one-quarter of Netflix subscribers said they would leave if it showed ads. The study found that Netflix might be able to keep some of those viewers if it lowered the subscription price to offset advertisements. It also found that Netflix subscribers will accept a price increase for an ad-free service.