A few weeks ago, CNBC posted a smart, in depth look at why so many investors were pumping cash into digital publishers focused on subscriptions over advertising. Yet in the post, Group Nine CEO Ben Lerer defended much of the digital publishing world’s earlier focus on advertising-driven revenue models, arguing that there is still too much money tied up in TV.Soon enough, the thinking goes (as it has for about a decade), advertisers will get wise and start moving their TV budgets out of TV (where the ratings keep sliding) to digital media.Except what if they don’t.What if instead of TV ad money moving over to the web, it just goes away?Digital media is booming you say? It’s growing at 23% this year, per the IAB. Haven’t you noticed the duopoly duopolizing everything?All true. Except that’s not TV money. That’s largely, generally speaking, direct response advertising. Facebook, Google and Amazon thrive on DR, with a dash of brand money sprinkled in. The rest of the ad supported web just scrambles for the leftovers. With all the digital disruption, and deaths of magazines, classifieds, newspapers, etc TV has remained a remarkably resilient $70 billionish ad market in the US seemingly forever. Linear ratings are plummeting. And rates are higher than ever.That can’t last, right? No, surely not. But that doesn’t meant the money goes somewhere else.If fact, part of the reason there is so much fervor for OTT advertising is that TV advertisers feel like they have no place else to go. They don’t know how to replace that ‘reach 20 million Americans in one night and move stuff off the shelves this weekend’ effect of TV - so they’ll take anything that looks and smells like TV. However messy and limited OTT ads are right now.It’s not fair, but the ongoing fallout in digital media - from Vice and BuzzFeed missing numbers to Defy Media and Mic going away - brand advertisers may like branded content, and web series and other ‘brand oriented vehicles.” But they don’t see those vehicles as realistic TV replacements. Otherwise there wouldn’t be as much blood in the market. Advertisers speak with their budgets, and their budget decisions say they don’t believe in the branding power of a Mic/Vox/Thrillist/Uproxx/you name it produced sponsored piece of content or video on the same level as TV, as well produced as these sponsored pieces of content frequently are.Otherwise they’d be moving chunks of TV money in chunks, rather than a trickle.The big fear in the digital media business has to be: what happens when TV ratings become so unsustainable, and interruptive ads become so intolerable, that marketers don’t shift their TV money, but just pull it back entirely, and put it to work somewhere else?"Our belief is we're still in early innings of what business models look like in digital," Lerer told CNBC.Perhaps. However, it’s worth recalling a speech Hulu sales chief Peter Naylor gave the IAB when he was named chairman - in which he warned digital ad executives to stop grumbling about being entitled to their ‘fair share’ of budgets.That speech...was in 2012.The industry better hope whatever inning its in, nobody’s pitching a shutout.