Do coin show dealers sell cheap coins?
In reality there are no rare or scarce coins that are cheap. Most coins found at flea markets have been cleaned, damaged, or when it comes to the larger coins such as trade dollars or old 1800 silver dollars are fakes. It seems you are not a collector, but an accumulator. You need to set goals for a U.S. collection. World coins most of the time are inexpensive so a one coin each country is a good start or maybe a subject such as ships. At coin shows you have a little of everything and some dealers do have inexpensive coins starting at $1 and up. Most do not though. A local dealer that has any smarts at all will have a world coin box at around .25 cents each, a wheat cent box coins around .05 each, a box of mixed U.S. in low grade and some may be damaged for low mixed prices. When it comes to coins you get what you pay for. It is however wise to go through a dealers so called junk boxes for you never know what he may have missed or put in there by mistake.