Greed never enters into it if you to decide to put back that which you legally earned, no matter the words used to describe it. It is, as you said, self-sufficiency.
Also, I doubt that anyone who suspected someone was "hoarding" would be satisfied and forget the whole thing if they were told it was not "hoarding" but merely "stockpiling". Word games won't satisfy those who will want to make trouble for you. Best bet is, if the SHTF, to just keep your mouth shut if you are stockpiling or hoarding anything.
“Synonyms” does not mean they are identical, they hold similar attributes but can have some distinct use differences.
Different mental images appear when you describe either “personal preparation” and “stockpiling” versus “hoarding”. There is a negative connotation to “hoarding” as to opposed to a person building up provisions before a disaster, or for winter. They don’t have “stockpiling limits”, they are “hoarding limits”. Anytime a disaster hits they talk about people “hoarding” not those evil people who stockpiled their supplies a year or two in advance.
Please tell me you understand the point, I’m getting rather tired of having to explain everything to the nth degree here.
And you are totally correct about not saying anything in the first place to anyone else about what you have or don’t have. It’s nobody else’s business.