I've not seen too much of such spam, but I have found a fair few accounts that seem to be in the UK and only seem to do a post or two talking about their business. I wonder if someone is providing that as a service to boost their SEO.
So far the spam here has not been as bad as you might expect. That may be down to the cost of creating accounts.
There may be some value in preventing spam from being indexed, but others will know more about that than me. We already have people saying they are censored by downvotes, but their content will remain. Someone could provide a front end that showed everything. These are some of the challenges we will face as Hive grows.