1) А чего это мы такие ворчливые?
=? Why is it that you ...
2) Не знаю, как такому, как ты, удалось сделать ...
=? I don't know how such a thing, how you managed to do ...
The functions of the words "это" and "такому" placed after the interrogative pronouns got me thinking. I'm assuming both "это" and "такому" can be omitted, so by placing these seemingly extra words, can you emphasise your statement?
(Incidentally, why say "как такому" in dative rather than "как такое"?)
I wonder if "чего это" and "как такому" are both used only in colloquial style, as these two phrases come from chatty IMs that my girlfriend sent to me.
why say "как такому" in dative rather than "как такое"
- because it describes you, not the thing you did. "как такому [человеку], как ты ( == какой ты есть), ...." //"это" and "такому" can be omitted
- "это" is redundant and used for spectacular exaggeration, can be omitted. "такому" builds the semantic structure, specifies what exactly caused an amusement, so can not be dropped.