Possible Bug - Ritual & Expedition Tablets drop mainly when they occur "naturally"

Hi
I complained about Ritual Tablets being rare on reddit and I got an answer that they drop often when you do the content as naturally accuring random content.
That made me realised I have very little both Ritual & Expedition Tablets and I remember getting some of them when not actually doing the mechanic via Tablet.
I initially thought that this might to "break you into" a mechanic so you have high chance to get the tablet, but while doing the mechanic very few tablets drop if any. I was doing mostly Abyss with Ritual/Expedition and I have 50 abyss tablets, but 4 Ritual tablets and 5 Expedition Tablets.

Could this be possible bug or unintentional problem caused by 0.3's Tower rework where these rituals were always "naturally" occuring by the map mod?

I remember back then those one use Tablets were plentiful, then they got reworked in Tower patch to be used like we use them now. But at that time I was already swimming in them so I didn't notice and I had remaining Ritual "naturally" occuring also as left overs from pre-Patch.