the label names might be longer now, but when your programming using the register and op codes which names are around 2-5 letters long it makes it seem very cumbersome to have lengthy names.
i use the Variable denomination simply because i find it hard to remember every little variable i make. Particularly when your making larger games with complex engines, although you'll only be working on one little bit at a time just having some form of overview to what it is
lp (strings), f (float), i (integer), p (pointer), v (vector), etc...
although i can easily just dismiss the standard types - when it comes to my structured types its good to keep track.
although v could stand for vector2,3,4 and even be either an interger of float vector, its good to know that it is a vector type then i can look at it at a glance and remember exactly what the entire function is for
i know alot of people don't like that sort of thing, and i've now got out of the habit of labelling everything which i got when i first started, i now use it as a reminder system as my memory isn't as good as most peoples.