Chat etiquette: Hi every time you start?

I have some people that I “talk” to a lot via Whatsapp, iMessage, Messenger and the likes.

And it kinda annoys me when they say “hi!” every f’in time we restart the discussion.

I think the reason for this is that I see it as a continuous discussion, with bigger breaks, while they see it as different chats/discussions every time.

Well… it’s not like a phone call, ok? :)