UJM, the gemara does not say “We are obligated”. It says we are permitted. Without that gemara it would be forbidden.
But the gemara is not addressing an individual, who is dealing with his own money, and has the right to squander it on things that are not tzedaka, if it makes him feel good. It’s addressing a gabbai tzedaka, who is dealing with hekdesh money and has an obligation to be careful with it.