He could, but she's not a normal person, she's a stunningly beautiful and charming woman who is his girlfriends best friend. If anything he's emphasising his politness so it CAN'T be misconstrued.
That's not helping the impression for me that he can't say good-bye to her like a normal person because she's hot. It just still reads to me like there's this constant undercurrent of the writer trying to show that Terry's particularly cool and attractive (including giving him a sleazy bachelor party so he can stand apart from it) that doesn't come across that way to me--thus the feeling of creepiness.