The front glass can be replaced and it's not that hard. All it takes is a little heat, a thin piece of wire (like a guitar string or piano wire), electronic parts cleaner, a new glass with adhesive, small roller, and a vacuum source of some type (like a vacuum pump or vacuum food sealer machines)
Apple replaces the screen glass by the hundreds and sells the phones as "refurbished". But for about $50, the average person can do it or pay someone with the equipment $100 or so to do it. That's way less than $200-$300 for a new digitizer assembly.