In your experience, at around what age did you stop getting asked for ID when purchasing alcohol at a restaurant or a shop?

In America, I believe you're required by law to request for ID when you're selling alcohol at a bar, shop, or restaurant. But people won't ask for ID when it's super obvious that you're over 21 just by your looks. So for yourself and for people you know, at around what age did you notice that you stopped getting asked for ID when buying alcohol at shops or restaurants?