If the Korean conflict was a proxy war between communism and imperial-capitalism, then one can't ignore the irony of finding a Century 21 advertisement among the pages of a book that celebrates the victory over such western ideologies. Temporary ideological confusion? No, not really. As a hyper-capitalistic nation, the Chinese publishers merely paint what sells, even if its advertisements are in conflict with its content.
If writing about China's glorious anti-capitalistic past helps bring in the dollars, then by all means, revel in the celebration of anti-capitalism! Why worry about ideological confusion when there is a dollar to be made?