The rec who keeps looking at your stack before he acts is thinking about implied odds he doesn't understand. He's not calculating - he's intimidated. A big stack intimidates him into folding more.

Why they do it

Recreational players who check your stack are not sophisticated stack-to-pot ratio thinkers. They're scared of how much you could potentially win from them. A big stack reads as a threat even when it shouldn't.

The adjustment

When you have a big stack and this player is in the hand, apply pressure. Your stack is doing work for you before you even bet. Use it.

What it's worth

Table image built on a big stack gets folds from recreational players who would otherwise call. That's free equity you're not paying for. Don't waste it by playing timid.