(1)Not their role. VKS AD batteries cover important objects in the rear, as well as provide general overlapping area defense.
They aren't there to ambush things, and they can afford not to.
(2) Far more range than competition, 3rd party OtH targeting capability, Active seekers.
48N6 and 40N6 are seriously fast, their effective range extends deep into Ukraine.
(3)VKS also have effective interceptors, also reaching deep into Ukraine. Those see their own targets thrmselves, even when they're at the deck, too.
(4)Finally, land forces have their own S-300V4, both as standalone army level units and as separate TELs integrated into corps level Buk batteries.
It's their job.
Ukraine does S-300/Patriot "raids" not because they want to, but because their army AA is technologically and numerically inferior, and there is no other way to suppress VKS strikes.