So my guess is that people would end up buying upvotes at a financial loss. So then buying upvotes would become a method of promotion.

The times I've purchased the votes from randowhale (maybe 8 or so), it was slightly profitable when taking everything into account. The one time I used booster, it wasn't profitable, but that has a different voting structure than rando. But, you may be right about where things are trending toward. I wouldn't be so against this if the STEEM/SBD were burned or if it was put into a Steem marketing fund or something similar.