I don't know what the standard etiquette is here but my guess is he is upset that he has no chance of getting immediate position on a fish?
Personally, I tend to sit directly across from them. At a 9 max table, I like to choose the seat 4 to their right. This way there are 3 seats between us to my left and 4 seats between us to our right, giving me better odds that the fish sits to my right
I dunno if that theory works in practice but it sounds good so I do it, and regs never seem to have a problem with me sitting across the table as its pretty neutral.