I'm not going to an old classmate's funeral
Is there a reason why you don't want to go?
I don't see the point of visiting graves when I can't talk to them like I did when they were alive.
If you are invited to a funeral it's rude to not honor them in their passing. Even if it's just a token gesture sometimes it's needed.
I do not agree and That's why I'm not going.
If that's how you feel, then it's your decision and I hope you can find other ways to honor their memory. The family may not agree with you, so I hope you are ready for anything they could say about this.