People prefer them because they're not Chita, the most annoying character, and because they're attractive girls in a romcom about attractive girls*
That's the "hard truth".
Saying Anjou and Toyoda are "gooner bait" (words used to have a meaning) when the whole freaking manga is heavy in fanservice es wild. Have you seen the covers? If you're reading Anjou-san, you like sexy girls, and you're gonna get sexy girls. There's no bait in there.
If Chita was sexy or cute, but had the same personality, people would still hate her