Because mascots bring tons of publicity and thus cred to the athletic programs of lesser schools.
Who gives a rat's ass about Western Kentucky U? Plenty of people, and why?

They have a cuddly, lovable giant pimple for a mascot! Hell, I'd root for their team if I saw this happy pimple about to squirt some puss-y school pride all over the field!
Smith: you need Sophie the Squirrel.
Let's talk.