It sounds that you may be right that some of the lower grades of Stainless steel such as Chinese made 200 series grade are making it into supposedly food grade utensils such as cups, bottles and vacuum flasks.
Even then it is not a good idea to use Hypochlorites (Bleach) for disinfection even with 304 and 316 food grade stainless. There are other ways to clean and disinfect such as steam cleaning.
http://www.bssa.org.uk/topics.php?article=45&featured=1Is 316 type the only stainless steel that is classed as the 'food' grade?
The '316' grades (1.4401 / 1.4404) are often referred to as the 'food' grades.
There is no known official classification for this and so, depending on the application, the equally common 1.4301 and 1.4016 grades may be suitable for food processing and handling, bearing in mind that in general terms the corrosion resistance ranking of grades can be taken as: -
1.4401/1.4404 (316 types) > 1.4301 (304 types) > 1.4016 (430 types)
304 is referred to as 18/10 or 18/8
430 is referred to as 18/0
The surface finish of many stainless steels also have an important function to the corrosion resistant qualities.
http://www.bssa.org.uk/cms/File/surfacefinishbssaVer2.pdf 
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