If you're always camping with a large household, it makes sense to buy a large tent. You'll need it for entertaining when the weather's bad. If you're the only one going to a particular event, you're stuck with setting up that large tent by yourself, or leaving it at home and taking the dome tent instead. If there are a lot of you going, and you expect to accomodate both entertaining in the tent and sleeping everybody inside, those two needs are going to have to be juggled. So unless you're buying tentage for the entire household, you're better off with a smaller tent for your personal use.
Smaller tents take less time to set up and strike, freeing time for other things.
And they're easier to transport. Getting Around Which brings up a second point. When you buy a tent, you must give some thought to how you're going to transport it. The larger the tent, the more space you must devote to it, which means less room for everything else you need to carry. Folks sometimes regret their purchase of a big tent when they realize that vehicles like vans, trucks, and trailers become necessities.