Why do people underrate these two items?

Especially when behind in a lane or when you have a bad team fighting comp. They give you gold too. I'd say one of these (ZZ"Rott) can effectivly push a lane (or freeze it) when down 1-2 towers in that lane. They have so much map pressure as well. Best of all, they are click and forget. No babysitting needed. Now, I do admit that as the ranks go higher they have less impact. Also with large premades. But for low level solos and duos. These items are great. I love annoying people with these. The portal is great for pushing side lanes while banner helps sieging.

On a side note, it may be a good idea to match the enemy's portal count wise. Them having 2-3 portals out (quite possible with a ) will become a side lane managing hell for your team. All the while they group 5 mid and push because they have no lanes ushing onto them and can force a 5v4 if your teammate goes to stop a side wave.