The reality is that everyone that follows the first person to buy the drink never actually pays anything forward, he or she just passes the one drink to the next person in line. There is no accumulation of drinks, only the single drink that keeps getting rejected as person after person is asked if he or she would like to pay it forward.
If the person in front of you buys your drink, you are not doing anyone any favors by not accepting the drink. You are not actually paying anything forward. You are simply taking that act of kindness and transferring it to someone else.
There isn’t necessarily anything wrong with that. It is okay to give the next person a drink that was intended for you, especially if you do not need to have your drink paid for. However, the logic flaw that exists in a pay-it-forward chain is to believe that you have done something good for the next person by simply purchasing your own drink.
The next time that you get caught in a pay-it-forward scheme. Do not be cowed into continuing it. Instead make a conscious choice between “Having a free drink makes my day,” “someone else is going to need this drink more than I do” or “I really do want to pay it forward. I am going to add a second drink to the tally.”