Well, I think the concern is that tweeting particular Steemit posts might make them more prominent and therefore more profitable, somehow 'monetizing' the whole Twitter+Steemit combo. I don't see that as a problem either, in fact quite the opposite - well rewarded content is usually considered more interesting by potential investors (nobody wants to invest in coins which create no traction).
And even if such 'monetization' is really a concern to someone, lack of content is obviously a far bigger concern currently.
I see. I agree with you that shouldn't be too much of a concern. We could easily hold the Twitter admins accountable to tweet posts equitably according to neutral criteria e.g. quality and relevance.
And anyway, it seems like any 'abuse' that could potentially happen would amount to such small profits that it wouldn't really matter...