You think that, but it's super noticeable. Muliple times I've been in a situation where I'm in a conversation with someone who is constantly glancing at their watch. Depending on how well I know them, I either say, "You you like to just look at your phone?" or "Is time moving faster on your side of the table, because you seem to be very concerned with your watch."
Or I say nothing and just think about how rude that person is.