Why do Liberal-Democrats...?

To the dumbasses on both sides acting all high and mighty.
Anon prevents blocking and harassment from your political enemies. 
Anon are less likely to be stalked, trolled, targeted and suspended by liberal internet bullies also. 

for the same reason conservative republicans do

Why does anyone post under anonymous?

Well john, lots of people do that. People of different views or political affiliations. Yeah, "Anonymous"? it's sort of a thing, been goin' on a while now. Glad you caught up.

I don't like that anyone does. Like the guy that posts under Anonymous and tries to trigger Democrats all day long with false statements - and rarely questions. Be a "man".

Seems more like conservatives to me.

Nice try, John. Maybe try for a question next time.