This is the problem I have as well. With a group new to D&D, it’s not so bad - they’re likely to take creatures which are cool, but not necessarily stealthiest or most fitting - it’s okay to have the bandit ask “…wait, why is a raven this far into a giant underground mine?”

Then you have the veteran players who have invisible, indefinite, sometimes incorporeal familiars… the most egregious was one who would cast through his nigh-undetectable familiar, making many encounters moot as the familiar could just ping down stuff without ever being spotted in return.