Ah, this again.
The mega corporation did not receive any tax benefit from collecting donations. They are able to write off the amount of donations from their income, so that they aren't paying tax on the money they collected specifically to be donated.
- Company collects $1 donation from customer
- Company has $1 extra income
- Company donates $1 to charity
- Company writes that dollar off of their income.
- Company reports the exact same profit/loss as if they had not collected donations.