memes

Depends on implementation.

There's a hierarchy called cardinality, and any two infinitives that can be cleanly mapped 1:1 are considered equal even if one "looks" bigger, like in the example from OP where you can map 100x 1 dollar bills to each 100 dollar bill into infinity and not encounter any "unmappable" units, etc.

So filling an infinite 3D volume with paper bills is practically equivalent to filling a line within the volume, because you can map an infinite line onto a growing spiral or cube where you keep adding more units to fill one surface. If you OTOH assumed bills with zero thickness you can have some fun with cardinalities and have different sized of infinities!