These pagers were bought by Hesbollah

All we know is that a bunch of exploding pagers were distributed through Lebanon. The IDF claims they were given to Hezbollah agents, but they've been caught lying regularly.

At least 12 people were killed after the attacks,[60][1][61] and more than 2,750 were wounded.[5][6] Civilians were also killed,[10][13][14] including four healthcare workers[62] and two children.[63] It is not clear if only Hezbollah members were carrying the pagers.[19] Lebanese Health Minister Firass Abiad said the vast majority of those being treated in emergency rooms were in civilian clothing and their Hezbollah affiliation was unclear.[64] He added the casualties included elderly people as well as young children. According to the Lebanese Health Ministry, healthcare workers were also injured and it advised all healthcare workers to discard their pagers.[64][65]

Uhhh, because these were bombs - bombs that were remotely and indiscriminately detonated. Some of the people were driving, some standing next to children or on busses full of people. There are reports of children who died because they were standing next to a target at head-level with the pager.There's no guarantee they were even being carried by "Hezbollah's guys".

I don't even know why anyone would assume otherwise. This was a loosely targeted terror attack

Because anyone within 5 meters of the pager also was hurt.