Another question (that's what this is hear for right

)
I just bought some tins that are from 2006 (mainly Frog Morton stuff):
1. When I shake the tin it sounds like the tobacco might be dry(er), (note, bought from a brother here, and not saying anything bad because I know re-hydrating is easy and I'm 100% happy with the purchase, just wanted to ask the ?) is this just me being a newb, but my question is, doesn't the sealed tin keep the tobacco moist/optimal?
2. Should I invest in the small mason jars to have on hand for right when I open a tin? Or can I keep the tobacco in the tin for a few (days, weeks, months) with it holding proper humidity?
3.Thanks!!