From a customer’s perspective, when I enter a shop and no one is around but I hear the “ding dong” chime I actually feel comforted in the knowledge that the shopkeeper knows I’m there.
I’ve not seen such a project before but it sounds like a fun one to think about. The challenge is distinguishing between someone entering verses someone exiting. Months ago someone posted on this forum a paper where a couple of people wired up some PIRs and wrote some learning code that allowed them to sense not just motion but the direction of that motion. With that I bet you would be able to know when someone is entering or leaving at which point counting is easy.
You will still have edge cases so the count will never be 100% accurate (e.g. someone starting to come in but changes their mind before fully entering) but it could get you really close.