Many people don’t have the means/knowledge/time to make a homemade Frappuccino, nor own an espresso machine. But yea if someone is paying $8 to wait 20 mins for a normal-ass filter coffee, they’re really lost.
Pro tip: look up Frappuccino recipes online if you don’t wanna pay the money. The reason many attempts seem off is because people don’t add an emulsifier. It will thicken up the drink and keep it from separating. A really tiny amount of xanthan gum is all it takes. I’m not sure what emulsifier(s) are in the proprietary Starbucks Frappuccino base powder, but it’s close enough.