Why do people in Pune spit so much?

Everyday when I commute on my two-wheeler, not a single day goes by without seeing anyone spit in front of me. First of all, itna saliva muh mein aata kahan se hai? Second, haven't people learnt in school that one should not spit like this due to spread of diseases? Wasn't one Covid lockdown enough that people want another one? But seriously, WHY? And how does their mouth generate so much saliva? Once, I was riding and there was a couple on a bike ahead of me. The man hadn't even drank a single drop of water, instead he was constantly chatting with his partner, when suddenly he sprayed out like half litre of spit. I'm not talking only about guthka/paan masala spitting, but I've seen people normally spit a lot. Even lads as young as 16 year olds.