riddle - We're found in vans, in bags, on bikes - we're found in books, in maps, online

We're found in vans, in bags, on bikes,
Most everywhere that people dwell.
Dogs may hate us, but we bring
Important tidings, good or bad.

We're found in books, in maps, online,

Most everywhere that info dwells.
China may hate us, but we're here:
Even in this riddle, you know.

What are we?

Answer

I'm guessing the answer is:

Letters?

We're found in vans, in bags, on bikes,

Postal vans, postmen carry bags and ride bikes, and all of these have letters

Most everywhere that people dwell.

And postal services are present in most populated areas

Dogs may hate us, but we bring

Dogs chasing postmen is a long-running trope

Important tidings, good or bad.

Letters carry news (e.g. in the past, news of a child being born, or a death)

We're found in books, in maps, online,

Letters of the alphabet

Most everywhere that info dwells.

A lot of information is written down with letters (most, because some information is pictorial)

China may hate us, but we're here:

Chinese writing uses logograms, which are pictorial representations of words (similar to Egyptian hieroglyphics); these are not letters

Edit - @Apep pointed out in the comments that this probably refers to China banning the letter 'N', which does fit the riddle much better.

Even in this riddle, you know.

Letters make up this riddle