Don't be upset. 30 secs is not long to hold. I have waited a lot longer than that, even to the point where I have forgotten I was on hold and left the receiver just sitting there .
That has happened to me before, maybe that's why I hate holds lol but this was a company (AT&T) who probably had 50 people before me so I understand that I must wait my turn. This was my boyfriend, who was talking to me first and told me to hold on IN THE MIDDLE OF MY STORY! lol I'm not mad at him (how could I stay mad at him?) but I believe I was right when I said it's rude.