I saw you get that downvote. I think ultimately some people will view it as spam unless they request the message and some appreciate the gift even if its a promotion.
Personally I see it as a promotion that gives something for free with no strings attached. Like those food stalls that let you eat a tiny piece of food.
Lot's of whale accounts have their idea on what everyone should do and if they don't do that they down vote sometimes down vote everything they do until they quit steemit. I guess they think they have some sort of authority. What you doing is fine, don't worry.
RE: Debate - Do you think sending mass memos is spam?