Polyethylene blown film does not have to be inconsistent.
If your low priced PE film is inconsistent within the same lot, your blown film supplier probably has used off-grade resins to save money on their major cost: PE resin. The thinking is "the customer won't know the difference." You do know the difference because the film doesn't seal or shrink like it did 2 hours ago after you readjusted the packaging machine settings for the third time today. You could deal with it if the film was just consistent within the same pallet.
Shrink film is a favorite dumping ground for extruders. Just about any PE resin will shrink, so it's tempting to blend in repro and literally floorsweep.
Problem: If you are buying printed film, laminations or bags, you are at least one step removed from the film supplier. You have no way of knowing if you are getting film from the same source every time. Even if the film does come from the same source, there is a good chance their extruder has switched resins to lower cost.
You don't have to live like this. When you get sick of it, give us a chance to prove continuity of supply in blown film is available.