Those of us in ministry, and those who work as volunteers in church and society, don't do it for the thanks. We really don't.
But when someone takes time to say thank you, to write a note, to share gratitude for something which was done for them, there is a connection there which is Divine.
Gratitude is part of living life to the full, it is part of what can expand our hearts and minds - in our attitudes towards one another, towards ourselves, and towards God. When we start from a place of gratitude, there is less room for fear or greed - in recognizing the giftedness of all we have, we begin the move towards generosity, the movement from a mentality (or Theology) of scarcity to a mentality (or theology) of abundance.
O give thanks to the Lord, for God is good;
for her steadfast love endures for ever. Psalm 107.1