Hi,
This is indeed expected behavior, and following feedback from the field, we acknowledge that it's problematic behavior for some customers.
As I wrote in a previous reply, we're working on a solution that will try to keep the rule value in the log with the data of the admin's main ordered layer, and also give some control over that.
In the meanwhile, a possible workaround is to move the Playblocks ordered layer to be last instead of first. Since the rule field in the log takes the first layer by default, it will keep your layer's rules in the logs, instead of Playblock's matching rules.
There are a couple of caveats to this solution:
1) You'll have partial visibility to what Playblocks is potentially blocking, as anything blocked in your policy won't reach evaluation in Playblocks' layer.
2) You won't get the performance benefits of an "early block" by Playblocks when it's preventing external scanners and other bulk attackers.
Still, it's a reasonable temporary solution if the issue in the log is a significant bother.
And as I stated above, hopefully we'll release a better permanent solution soon.