I can guess, some gamblers are self absorbed monomaniacs it inevitable they start winding other punters up, I could write a long list but some of the common ones.
1. anoying cheering, jockeys rather than horses, distracting and you cant hear the commentry or understand what one theyve backed...
Sounds a bit like the architype "Pub bore" of the bookies, his comments say as much. A pro gambler would at least shop around for best prices. I told one to shut up about his inside info as none of them won, he wont talk to me now. It depends if he and his cronies are pissing of other punters...