Earlier quoted context omitted.
PiHole and PFBlockerng are two big ones that use these resources too and setting those up it struck me as it did you that simply polling these resources on a set schedule was a waste. Podcasting 2.0 has been talking about podping as a solution because podcasting basically has the same problem with periodic polling of the RSS feed. Basically you subscribe and then receive notice there's been an update, THEN you go get…
The difference is pihole only updates weekly.
PFBlocker seems to default to once a day.