So you're saying that because TBS will be broadcasting first-run episodes of American Dad, it will have the right to distribute the episodes to AS for syndication? American Dad won't actually be owned by TBS in 2014; it'll still be owned by 20th Century Fox, the same way Futurama was still owned by 20th Century Fox during its Comedy Central run.
It's already been confirmed that the eleventh season of American Dad will initially air on TBS, with encores following on Adult Swim ultimately joining the daily rotation. I'm confused as to why you're adamant that first-run production & syndication arrangements must be hammered out in separate, network-specific contracts, because as illustrated by AD, it's untrue. Pricing is based on contracts, and a single, bundled price may be offered to a parent covering a blanket of networks (and that parent will exercise cost accounting standards to create internal costs). Reportedly, Fox has began shopping The Simpsons around (which likely means the series is/will be ending) and due to the high costs associated with the acquiring the series, it will be offered with flexible terms so that any parent company acquiring the series may spread it among their umbrella of networks.
It's also commonplace for networks to add contract clauses enabling them to gain a piece of the syndication rights. Circa 2007, CBS, for example, guaranteed orders for 110-episodes of 20 Century-owned How I Met Your Mother if it obtained a certain threshold in syndication fees for them. And last year, TBS renewed ABC's Cougar Town but reportedly received rights to some syndication fees (terrestrial & future cable). Comedy Central (Viacom) likely earns some fees from terrestrial syndication of Futurama as well as those from global broadcasts.
In your original post, you were making it sound like TBS purchasing the syndication rights to The Big Bang Theory, which is currently still on the air, is the same as TBS picking up American Dad after it was canceled by Fox. As someone mentioned above, first-run production costs and syndication costs are not coming from the same budget. The people at TBS who decided to pick up TBBT's syndication rights are not the same folks who decided that new American Dad episodes would be a good investment.
That's a misnomer. There are no separate budgets for new production & syndication production; it's the same people who decide what content the network wants to air and at what cost. The reason you're seeing a surge in original content, including renewals of cancelled network series, among subscription providers is due to high costs in licensing (syndicating) content - up over 700% in just a few years, as I noted above. While first-run production is always going to be more expensive, the gap has closed & providers see value in offering exclusive content.
For example, earlier this year executives at Comedy Central needed to decide: Do we want to renew Futurama? Or do we want to consider licensing an off-network broadcast, such as Bob's Burgers? Maybe we'll produce another new series, such as a low-cost standup show. Or maybe our viewers are satisfied watching re-runs of Tosh.O or South Park.
It's definitely the same people making the decisions.