Border Crossings - Why are the Rules Always Changing?

I swear that every time I cross the border there are different rules.  Within one month, the experience can be totally different at the same exact border.

Last time, we got hustled into a van to pay the exit tax.  This time, I couldn't find the van and ended up scanning my passport through a legitimate machine that gave me a receipt.  It turns out, the other people did get hustled into a van and were charged extra for the "service fee."  I found the real machine by accident. Figures.

Then, when we got into Panama they decided they wanted to "check our bag" which was really just a guy demanding you write Tracopa in the line that says flight number (This doesn't even make sense because it is just the bus company name) and then telling you to take your bag.  He did not open a single bag.  Great customs check, Panama - my pineapple slice made it safely through to eat on the other side :] 

A person could have totally just not entered that bag checking room and nobody would have even noticed. 

I just hope that tomorrow my border crossing to CR is more successful than the last time.  Wish me luck!