A counterpoint is that occasionally, a team of squishy (even medium-range) champions ends up against a team of strong bruisers that just DEMOLISH them before they can get going. Like, you'll have a team with Yi, Teemo, Draven, Karthus, and Kog'maw versus a team like Jax, Singed, Blitzcrank, J4, and Rumble. While normally the longer-ranged first team would have an advantage, you can sometimes see the tanky high-early-damage team just jump on the squishies and demolish the other team before they can really leverage their poke.
Nautilus and Blitzcrank's grabs are unusually powerful on PG, since the 'awkwardly shuffle around before a teamfight phase' is what the majority of the map consists of.
Edit: Also, playing 'true melee' champions like Udyr, Garen, and Volibear is just infuriating. Bushes are nice, but if your only ranged option is "flash onto the other man", you're going to have trouble. At least one of the enemy 5 champions is going to have some kind of CC to keep you away, and god forbid you underestimate the damage that tower does and try to dive it early.