Listen to Granny because Granny always knows best!
I have no philosophical objection to gum chewing. If you wish to masticate plastic then that is fine by me.
Effing well dispose of it properly.
On the pavement.
Under the edge of the pub table.
Stuck to the wall next to wherever you are sitting.
Remove the disgusting globule from your gob. Wrap it in a tissue. And put it in the bin!
The other thing is more about aesthetics. You may think that chewing gum makes you look like James Dean. It don’t. You look like a fucking llama.
A stupid fucking llama.