"Sanitize, heat, seal, etc. otherwise it doesn't create an airtight seal like a ziploc does? I must've misunderstood."
There are two schools to what you've written. One says do all the things that you have in your list. The other says that this (the heating) is unnecessary. Personally I haven't created the low-pressure seal you describe in quite some time, but I do sterilize using very hot water, then cold water, then very hot, again. My seal consists of using a lid that is in good condition and tightening it atop the jarred tobacco as tight as I can. This does create a type of seal as you can tell from the rush of air into the jar after it's been shut for a year or two. With the lid screwed down sooooooo tightly, I very much doubt that the lack of a heat seal has allowed any more air/volatile compounds, etc into or out of that jar than had it been heat-sealed.