Sure, but if you've already built big rockets it's a lot easier to convert those to throw small objects into orbit than it is to build an entirely new rocket.
I've allways thought that clustering proven designs was a pretty good idea on their part.
They worked with what they had. However there's a big weight penalty, eventually limiting how heavy a "something" you can toss, and costing lots more in fuel and rocket components. Still those big clustered rockets are what is still used to loft the larger components of the Space Station. We take up the bulky but not so heavy stuff in the shuttle. They take up the not so bulky consumables, along with fresh "lifeboats" every so often.
Not sure your point ... the Saturn 5 was a cluster, and the shuttle uses the boosters and 3 main engines.