All the Chinese places I frequent have served the same "red" sauce.
I have found that the LaChoy Sweet & Sour sauce to be identical.
http://www.lachoy.com/products/sauces.jsp
I've tried that one. It's not the same. It's got little bits of bell pepper in it. And it's not just the bits of pepper or other stuff that ruin it. It's got a different flavor also.
http://www.foodservicedirect.com/product.cfm/p/3717/Sauce-Uncle-Bens-Sweet-&-Sour.htm
I'm thinking you didn't read the thread.
Are we talking about that bright red sweet and sour sauce? It's pretty easy to make. I do it all the time. Just combine equal parts water, sugar, ketchup, and white or rice vinegar. Simmer for 45 minutes and enjoy.
I've made several similar recipes. Those that include pineapple juice seem to be a closer match to what you find in the restaurant.
But I think you are all missing the point. Sure, I could make it or I could just buy it at the restaurant. I'm not asking how to get the same sweet and sour sauce. I'm just asking why the grocery stores don't carry anything that is identical to what you get at 90% of chinese restaurants.
I buy the frozen egg rolls and spring rolls from Costco and it would be nice if I could just pick up a bottle of bright red, semi-transparent, completely chunkless, restaurant style, sweet and sour sauce at my local grocery. If my kids want to throw some egg rolls in the oven for a snack (or a meal), I don't want to make sweet and sour. I just want to pull a bottle out of the fridge for them to use as a dipping sauce.
This is the stuff I used to buy when we lived in Oregon. It is identical to the stuff you get in restaurants.
http://www.alliedoldenglish.com/sunluck_items.php?flavor=restaurantsweetsour
Our grocery stores carry other Sun Luck products, but not the "Restaurant Style Sweet and Sour".