Originally Posted by CliffordK

I've wondered about that. Some online vendors sell tubes at about $1 to $3 each depending on the tube.

Yet, some local bike shops sell them for $8 each.

So, say $0.80 to $8.00 is 10x, or a 1000% markup... not bad

I don't like to inflate my tube immediately after patching if not going into a tire. But, I sometimes skip that step of checking my work, which could potentially lead to dire consequences.