Good for you.
Yes I would also have been appalled at seeing that in any store yet alone at the register.
I have some other 'bones of contention' with Chevron so do not use them at all. I will also print out your letter and email it to several of my friends (also in recovery.)
Don't know if it will do any good or not, but at least the word will be getting out.
That is absolutely disgusting!
Thank you for being "pro-active".
Love and hugs,