[RIMR]

The ads were for Facebook groups, so once they built up a decent subscriber count, they had an audience to propagandize to without paying.

As for the pro-LGBT/liberal ads: One of the strategies the Russians used here was to infiltrate and divide. Only propagandizing to one side of the American political spectrum isn't as effective as playing both sides and turning them against each other.

These ads are just the tip of the iceberg. There were still countless bots and sockpuppet accounts used to sway people one way or the other - but typically against one another.