The reason FBS and FCS won't merge is the same reason anything happens in college sports and life: money.
The 119 teams playing FCS football would have to add 22 scholarships for football; AND another 22 for a women's sport.
That's an average of about $1.1 million for the 48 FCS schools who's tuition were readily available on the USNews&WR site.
Now, they could decide to meet halfway: If they went to 74 scholarships instead of 85, the FBS schools would save about $600,000 a year.... but that savings including cutting 11 women's scholarships. And that's never a smart move politically.
The other big caveat is that some schools (PFL, NEC, Patriot, Ivy) play non-scholarship football. It would cost THEM up to $7 million a year to move to FBS. Butler (PFL) has a budget is like $2 million. So, they'd have to almost quadruple the size of their budget if they merged FCS and FBS.
Not to mention that the Ivy just wouldn't do it.
So by "merger," we'd really have to mean "eliminating the minimum scholarship requirements." Which basically makes 240 D-I college football teams; 120 playing with more scholarship players than the other 120, and 40 of them playing with none. And those not with the full allotment of scholarships would either play the same schedules they are playing now... or get killed if they played up.
You'd be eliminating the FCS playoffs, not to mention the effects on the BCS scheduling (four body-bag games at home, never play a non-conference game that matters), which would make the regular season much worse; and make conference alignment worth much more.
I don't think that works for anyone.
One interesting thing I pulled out of the research for this post, was that there's some FCS schools which could pull off the leap based on their relatively low tuition.
For example, the Dakotas. UND, NDSU, USD and SDSU. Based on the tuition reported by USN&WR, it could cost them $2,117,368 to add 44 scholarships. COMBINED. other schools who could possibly afford the leap:
Idaho State ($700,000)
Montana State ($802,912)
However, I should probably point out that ALL these numbers are TUITIONS, and might not include room & board.
Plus for 22 to 44 more scholarship athletes, you have to add trainers, secretaries, SIDs, etc; as well as coaches and operating costs for your new women's sport
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