I hate when people burping
Burbing is not a bad habit but i guess one should excuse before doing such act and if done unconciously the should pardn for their behaviour. As there have been many people around who just do this and think it is something funny, they should realize that this could be an act of embarrassment in the gathering rather an act of joy. so one should excuse if something like this happens as it would show their manners and would not makes someone who is with them embarrassed.
People do not bother what ever they do either consciously or unconsciously, some acts we do become our identity. well i believe that if one excuse for any such act that is a good habit but for those who do not do this they need to learn some manners to socialize among people.