i don't find it "wrong." i just find it "wrong for me." the real (and very subjective) answer is that all the spreadsheet uis i'm familiar with are very clicky (as in you wind up using the mouse a lot). when i'm at a computer rather than a touchscreen, i prefer to use a tiling wm and programs with keybindings. perhaps i just haven't taken as much time getting proficient with spreadsheets as i have with text editors. also, some people prefer using a mouse, and there's certainly nothing objectively wrong about that.

also, as i said in the previous comment -- and this is more objective, i think -- text files are more flexible than spreadsheets in that they don't impose any particular structure on the data you're entering. if you're populating a relational database, you're going to wind up having to put things in table format eventually, but perhaps you don't want to have to decide exactly what data you'll be entering from the moment you start entering it. in that case -- and perhaps this is going back to personal preference again -- i find it easier to rearrange a text file than a spreadsheet.