There are very few companies actually MAKING sporting optics from start to finish. You can get great glass from about anywhere, so long as you pay the oem glass house to do X,Y, or Z.
Almost all consumer glass is Japanese (you hope), Pacific Rim/China (you sigh, and gamble), or European (you pay through nose).
Burris, Millet, Leupold... these guys may assemble, coat, and QC in the states but the glass is Japanese. They just order it made to a certain level of quality, and break balls whaen it shows up not cutting it.
Simmons, tasco, Barska, NCstar, Leapers, weaver, Bushnell et-al do not, for the most part, pay these guys (pacific Rim, Japanese firms) to make them great glass. They pay them to make stuff they can use to corner marketshare in the sub $150 segment.