I haven't had this problem. Are people pasting links to someone else's post into their post or is this from boosts? Is it quotes? I don't think Mastodon has quote posts, but Firefish and potentially other Misskey variants do. Do you have an example? I primarily use Firefish instead of Mastodon so I am admittedly not the most experienced Mastodon user, but even when I scroll through my Mastodon account, posts and boosts open in my own server when I click them and I can star or bookmark or boost them myself from that page.
I am curious about what's happening exactly so I can understand it better, I hope my questions don't come off as hostile.