Aside from being hard to swallow..

You have chemicals in ur stomach called enzymes that break down the food so your body can absorb all that nutrients. When we chew food, we increase the surface area of it, meaning we break it down to smaller pieces. When the surface area is increased, the enzymes in your stomach are able to break down your food much quicker and easier. Think of it like if you put a 10g sugar cube into a cup of hot water and put 10g of sugar crystals into another cup of hot water which do u think will dissolve first? It’s gonna be the sugar crystals because all the sugar molecules can easily be reached rather than the cube because it still has to break down as it dissolves. Chewing works the same way. So technically you don’t have to chew your food because the enzymes in your stomach will break everything down anyway, but it’s nicer to have a healthy digestive system that will give you pain free toilet times ^^