Every tank is different. One tank that has a lot of fish and is fed a certain food may not need any food specifically fed for or to the corals. Other tanks will definitely need it, or certain corals will do better with spot feeding. It can depend a lot on the fish (type, size, and number), corals (types and numbers), tank size, food being fed to the fish, etc. There are many factors that will determine the need (or lack thereof) for coral foods.
Try different things, including stopping those things. See what happens. If you feed pellets to your LPS
and they seem to grow a little faster, or be a little more robust, keep feeding it. If you start feeding them, then stop, and don't see a difference, then that food wasn't making a significant difference. You can try this with different foods, feeding methods, etc. until you find what works best for your tank. Remember that more nutrients in to the system means more nutrients to for algae.