The bean curd though IMO isn't a good substitute for real cheese, I find it a little saltier than American Cheese which is salty enough. I do think people have an acquired taste for stuff like that though. Just be careful with the tofu's. I avoid the red ones in general due to it being too sweet.

Not noticeably sweet in N China, but salty, as are the white one and the smelly one.

Yep, two major factors at work here:
1) cost, which can be paramount!
2) additives, some are needed to preserve food, such as salt in olden days and nowadays!

I reckon you can remain healthy eating it if you avoid eating any other salty or sweet Chinese foods. When I cook, I NEVER add salt NOR sugar to any of my culinary concoctions, and my Chinese wife does so too, though unwillingly.
As for Chinese sauces, we should be careful. When we cook mutton hotpot, I use 'Dachongqing', which I've found to be salt-free. I'll even drink it during my 'mala' (spicy) meal. However, my wife adds from a packet sauce that is salt to her dipping bowll The Chinese in general don't know that salt and sugar are killers, though we, as westerners, know we need only minimal quantities of both in our diets.

Where I only intake extra sugar, maybe, is by drinking beer. So be it!

In the movie 'The Scent of a Woman', the line 'sugar is shit' is used. I couldn't agree more with that line.