You're right. The search engine on Steem also needs a lot help due to its inaccuracy; I'd suggest using https://asksteem.com instead of it.
I think the reason lots of people ask for "follow for follows" or spam "upvote me" on users' posts is because they see the potential of Steem through posts with hundreds of dollars of rewards on the trending page, but don't know how to get there.
So they put out a post, and see it earn less than a few cents of rewards, and get quickly disappointed. I've even seen a few people at this stage stop posting on Steemit, discouraged by low rewards.
Some of those who stay realize that they need widespread support from other users in order to gain real rewards, and start posting in the way you described, for better or for worse.
In the end, it's those who stay invested in the platform, those who constantly write high-quality content, and those who interact well with other users who win the most. This is why I think Steemit's old slogan was so great— "Come for the rewards, Stay for the Community."