Hi, there is no need to presume anything on the blockchain. I can just check your wallet and see your transfers of STEEM and SBD from Blocktrades.

If all new users did the same it would be great for the price of STEEM, it's a shame that most don't

I would definitely recommend continuing to purchase more and powering up whenever you can - it's much more enjoyable as your vote value increases, and hopefully it will turn out to be a good investment