The United States of America is the most generous country in the world over a long period of time according to the Charities Aid Foundation (CAF) World Giving Index. Unlike Czechia that is among the least charitable countries. Americans love helping out people in need. Donating money to charity seems much less common for Czechs. I believe it is not a lack of generosity.
Contactless payments are very popular in Europe as they are faster and more secure compared to swiping your plastic card or paying cash. However, as soon as you try Apple Pay, there is no chance you are going back to plastic.
The purpose of any charity event is to raise money for a good cause, right? So people should be aware that you are not only trying to get them to come to your event, but they will also have an opportunity for donating.