That's exactly what Matt Bors does in this cartoon.
I think every member of this site would agree that black people have been — and continue to be — the victims of numerous forms of discrimination, ranging from the subtle to the terrifying, in the United States.
But with all the injustices blacks have suffered and continue to suffer, being slighted because there's a National Sandwich Month isn't one of them.
According to this Wikipedia article, there are 35 commemorative months in the United States.
In addition to Black History Month (February) and National Sandwich Month (August), there are National Nutrition Month, Women's History Month, National Brain Injury Awareness Month and National Essential Tremor Awareness Month — and that's just in March.
May is the most popular month for designations. It's ALS Awareness Month, National Bike Month, South Asian Heritage Month, Haitian Heritage Month, Asian Pacific American Heritage Month, Asthma Awareness Month, National Pet Month, Celiac Awareness Month and Jewish American Heritage Month, and was National Guide Dog Month in 2008 and 2009.
This year, the National Frozen & Refrigerated Foods Association designated March "Frozen Food Month."
I really don't think they — or the person who came up with the National Sandwich Month designation — did it to demean black people by lessening the stature of Black History Month. Nor do I think anyone who actually celebrates either Frozen Food Month or National Sandwich Month is doing so to demean black people by lessening the stature of Black History Month. (They probably have too much time on their hands, but that's another story.)
What I do think is that Bors found a cheap way to play to Kossacks' sympathies and did so, without even the 30 seconds of research it took to prove that his point was actually pointless.