There's a few barriers to entry.
A) You need to be somewhat technical to set one up
And more importantly:
B) You need to have enough Steem Power to make anyone want to actually submit a bid to the bot. My bot is extremely tiny compared to most. Some bots have literally millions of Steem Power invested in them. Mine has 320 lol.
The more Steem Power the bot has, the more the bot can earn. The bots with millions of Steem Power are literally making thousands per day. Puppy Bot will be lucky to make a few dollars per day.
I've only seen 1 bot that is smaller than @puppybot so far. It's definitely a bit of a pay to play game right now.
And yes the post/comment cannot be older than 6 days.
I'm not sure if bots with millions of SP earn more. In absolute terms they do. But as percentage not necessarily.
Thegoldencobra has only 181SP 🧐
You just planted 0.19 tree(s)!
We have planted already 5828.67 trees
out of 1,000,000
Let's save and restore Abongphen Highland Forest
in Cameroonian village Kedjom-Keku!
My Steem Power = 20674.51
Thanks a lot!