For me the major benefits of blue barrels are that they are relatively rodent proof. I have had soft coolers and packs destroyed by raccoons and I have been run off of a nice island campsite in Quetico by starving squirrels. While blue barrels are certainly not bear proof in that a determined bear can crush one easily, they are watertight and virtually airtight and if you keep food odors off the barrel exterior a bear is much less likely to detect food in a blue barrel than in a soft pack or bag of some type. I know experienced northwoods trippers who ceased hanging food packs in the Boundary Waters or Quetico years ago. They keep food in barrels outside the camp perimeter, securing them between closely spaced tree trunks with straps and they report never having had a bear issue.
Having said that, blue barrels have some drawbacks apart from price and weight. They are not very comfortable to portage any distance although a decent harness makes it tolerable. They are very good at protecting your back from hard objects but rectangular items don’t always pack very efficiently in a cylindrical container. The locking rings are relatively easily damaged if you accidentally step on them. And blue barrels don’t always pack into canoes as efficiently as multiple soft packs can. Some canoes are narrow enough between the gunwales and have thwarts placed in such a way that it might be impossible to fit a 60 liter barrel into the boat as the barrels are usually too wide to slip beneath thwarts.
You can sometimes find used blue barrels at a good price on Facebook marketplace or ebay. These barrels are used to transport medications, spices, and other food stuffs and are usually not reused. People buy them at their points of destination and resell them for a small profit. I have acquired several of my barrels this way and they have been in good condition but some have retained a pretty strong food odor for some time.
You can find new barrels cheaper than $100. Here is a source for a 60 liter barrel for $64.65 but the ground shipping is an additional $21.49 to my zip code. Still a bit cheaper than $100.
If you don’t need to carry a lot of food and don’t want to pay for barrels you could go with one or more 5 gallon poly buckets with Gamma lids. You can buy Gamma lids on Amazon and they are not terribly expensive. The buckets are widely available at hardware stores and the like and usually only cost a few dollars. The Gamma lids have screw tops with a vinyl O ring and they are a press fit onto the top of the bucket. In order to insure that they are as watertight and airtight as possible I use silicone caulk around the underside between the Gamma lid ring and the bucket itself.
A 5 gallon bucket has a volume of 19 liters. The most common blue barrel sizes are 30 liters and 60 liters although they are made in a few other sizes. So a couple of 5 gallon buckets would have a total volume between that of a small barrel and a large barrel. And there are 6 and 7 gallon buckets that accept the same Gamma lid, although they are not as widely available.