Once you start sealing, you forget to stop
It really is such a versatile machine.
Re the bread: that is very hard to do because fresh bread contains air and the machine is made to extract air, so you'd end up with very stale but well sealed bread. It rather defeats the purpose. Bread is probably one of the few things that are almost impossible to seal. And the cheese is greasy so possibly a bit of grease got on one of the edges which makes that spot unsealable.
As for reusing bags, that is very tricky. If both sides are smooth, then a home machine has trouble extracting enough air to make the seal. That's why the special bags with one 'rough' side are made. Air can get out of the channels that also make it difficult for air to sneak back in through. And once airless, the bag can be sealed. Commercial machines work differently so it's basically a waste of effort to try to save smooth bags. I try to be economical with mine by bagging smaller, more useful quantities that I measure out for specific needs: eg, 8 cups oatmeal (which is our normal need for a few weeks).
There is a way around reusing bags
here. But I must point out that by doing so, you could void your warranty if something wrong happens.
I too try to be thrifty with the bags/rolls but as one lady said, we have to stop being cheap with them so we can get the proper job done.
BTW, if you're getting short on freezer space, have you considered dehydrating produce? I've been doing mushrooms, lemons, red peppers (from shops) among other things, I place the dried items in kilner jars and use the sealer attachment to seal the lid. It's been working out very well and saving no end of freezer space. Items can also be bag sealed and those bags stored in sealed buckets or big storage totes against rodents.
One of the best tututorials on this is
this gal. It's a multi sectioned topic, but not overly long, yet she thoroughly covers both dehydrating and sealing. I don't bother with the gloves myself.