My older sister always pressure canned green beans, and they were the only ones her family would eat -- never tinned ones. I grew up hearing stories about pressure canners blowing up, so I was very leery about getting one myself. I just bought a Presto 16 qt. pressure canner from Wal-Mart for less than $60.00 for our smal group canning sessions. Well, I found the Presto so easy to use, not scary at all, and have purchased one for myself, as well. :-) I had been considering an All American at around $200.00, which I understand is the Cadillac of canners.
I don't have a freezer, just the one in the fridge. I do have shelves in the basement, and canning keeps the fridge free for other things which can't be processed.
You're right that pressure canning hasn't been around forever. What we probably will never know is how many people didn't clean or prepare things right and may have died from botulism.