Change..Please?

I was attending mass last sunday with my GG and her brother. We were seated at the back side of the chruch. An elderly man caught my sight. He was thin, probably stands about 5'8" and was alone. He has difficulty standing and walking since he had a snail pace and was always clinging to walls and things he can cling on.
Another elderly woman caught my sight. She was probably early 60's. She had a nice dress, nice shoes, nice perfume and nice set of teeth. After the homily, it was now time for offertory. My girlfriend gave 20 pesos to the mass collector. The old man proudly waved his 20 peso bill in front of the collector. As the collector is making her way towards other church goers, she was stopped by a slight tapped in her shoulder. It was the elderly man, he is asking for a change. The church collector gave the old man 10 peso coin for a change.
The old woman I was mentioning earlier gave out a smile. She turned to her daughter I presumed and gave a smile.
I was dumbfounded that you can ask for a change in a church donation. Heck if I've known it earlier, I should have given what I really want to give, instead of skipping if I don't have something to give.
But looking back, I was ashamed at myself and marveled on how "Lolo" taught me a very wonderful lesson in life. Give what you can only give. This has got me thinking until I wrote this blog. He was right, we cannot give more than we can give. I mean, If we give less that we can give, we will have a guilt feeling of not giving enough. But if we give more than we can give, we tend to blame ourselves by giving too much and not thinking about our future.
But GOD openly discuss that whatever you give, He will give it back, tenfold. I just wish GOD will give "Lolo" many years to live and may his honesty rub to every person he meets, especially in church.