In their defense, sources do not have to wait to get merits before they can give (unless they have run out or source merits), and the suggestion only includes merit sources.
Good point, I missed the "sources" in my own quote. But still, it's better to leave it up to the sources. In that case, OP should complain to theymos:
If they complain about amounts, tell them to complain to me.
It's best if sources try to exhaust their source allocations, even if it means giving posts higher amounts than is typical. If you have 150 source merit and you only see 3 merit-worthy posts in a month, then I'd rather you over-give each of them 50 merit than let the merit expire. That way there are more people capable of sending merit, and the "merit economy" is less top-down.
As a Merit source, I started by giving one at a time. Nowadays I mostly give 4 or more, because I can't keep up with less. So it will depend on the user's source amount.