While one could drill holes in each bay and dense pack those areas with cellulose or fiberglass - that would generally not be a good idea.
- The main reason for that is, if any water managed to seep in through the walls you would end up with a moldy rotting mess.
- The only product that should be used where it would contact the exterior basement walls is closed cell foam and to my knowledge they do not have a pourable version.
If you have not done so already and want to lower your heating needs - look up and deal with the rim joist area with all those penetrations.
The next stop would be up towards the attic - air sealing and insulating those areas.
For more information:
Read "What's the best way to insulate the underground walls in our basement?" a Q&A answered by Michael Holcomb.