Why do tiny bottles the size of $1 hand sanitizers exist? Does people’s difference tolerance levels play a factor for the sell of such tiny containers of alcohol? And same for tiny glass shots the size of a golf battle?

Went to an ABC store with my uncle and he bought different drinks. However when he started drinking at home he specifically gave me a tiny bourbon the size of your hand sanitizer thats for sell at the cashier register counter at Walmart for $1.52 and he explained to me since I’m not used to alcohol I won’t be able to drink like he does. The moment I took a sip, I had difficulty gulping it in and I couldn’t even finish the small Bourbon bottle, stopping at around a 3rd of it.

So I’m wondering if the existence of this tiny size is because not all people can take in alcoholic beverages equally unlike say a typical bottle of Pepsi and a glass of ice tea at a restaurant? That its meant for light drinkers and people like me who barely have any prior drinking feats? And also hence why tiny glass shots the size of tiny ball like ping pong or golf or even as small as an ice cube exists in bar?