Yeah, I guess so. However especially for the college, they probably deliberately not only named some of the characters after SOL: Clubs (IIRC: Emma, Veronica), but also put the badges on their uniforms are identical to that in SOL: Clubs. There was an eerie deja vu when I saw the badges and I was like... ? I've seen this somewhere before...
Although I do understand that they might've just reused the stuff from SOL: Clubs. xD. I certainly have seen multiple VNs use the same backdrops and settings as others.