But there are really good games on roblox, such as polyguns, appoc. rising, etc.
in Growtopia you only have a "World" and that it, I have played both games but i do enjoy Roblox more due to the fact it does not cost that much to look "Okay" in roblox rather than farming for hours on end getting like 1-2 world locks to buy cheap looking clothing, roblox has a programming language named LUA which makes it so that you can make anything you possibly want via "Scripting", Also you are more liable to get scammed on Growtopia rather than Roblox.