Name means a lot and Kakashi's moniker has earned him quite the reputation. If he only came with Sakura they'd assume she was either a subordinate and that Konoha's really spread thin, or that she's someone important to him. They aren't aware it's both. The shinobi she fought in the forest were special, but the ones I'm talking about will be basically fodder, but threatening fodder for someone of her level. So they can focus on Sakura and lure her away, and try to use her against Kakashi. Even if Taro is skilled in his own right, he won't want to take much chance against someone like Kakashi. So, yes, they underestimate Sakura to the point she can inflict some damage. Taro's the smart one, but his Sound Ninja grunts are not so smart.

They can either flee to bait her into following since Kakashi isn't around, or they can signal for reinforcements to overwhelm and capture her. What do you want to do?