I don't see any problem with the blankets on the infantry. What soldier doesn't want a T H I C C blanket for nap time?
The reason is because it covers the soldier from cavalry attack from sabre's or lancer's which is why often in battle you see it being worn ( that and the fact if you leave it be somebody might nick it) but there was a video from some Prussian Reenactor ( cant remember when or where) that explains the full usage of these thick and solid blanket rolls, it decrease the chance of you being stabbed, because it means the sword or lance or bayonet will have to go through 4 layers of item before it stab the human body, not to mention sometimes these things have a leather cover aswell.
in fact often times i see illustration where they would try make the roll very thick even if it shorten the lengtht of the cover, it still kept your chest and stomach from being stabbed, sometimes i do wonder in a combat situation where a Prussian Regiment face off with french one, how would a bayonet work when both side have two things that does the same defence